Holistic Review: One of the few two-parters of the revival to truly justify its extended length, by slowly unravelling a complex mystery with the aid of time-travel.

Under the Lake got on my good side almost immediately. It has a delightful classic-series feel right from the start, as the Doctor and Clara explore the abandoned corridors of the Drum, bolstered by the way the story practically epitomizes the "base under siege" archetype. I've been trying to pin down exactly why I like this story so much, and I think what it boils down to is that even if some of the elements feel recycled — take, for example, the appearance of Pritchard's ghost, which hits all the classic horror beats — they're just so well done, and the plot is so solid, that the net effect is very positive. And the setting in this case is a really original one: an underwater petroleum mining base situated next to a flooded faux-Russian military training village. Sadly, very little of this setting has any real impact on the plot, but it lends great background color. I'm well aware that this story isn't destined to be one of my top favorites, but it's refreshing to see a story that's clearly been thought through with great care.

The plot is indeed very well structured, and it's probably one of Toby Whithouse's best scripts for the series. Part 1 thoroughly explores the setting, milking a great deal of tension out of the idea of ghosts stalking an underwater base, on which there's only one safe place to hide come nightfall. It sets up so many mysteries to which I couldn't even guess at the answers, and gradually reveals the most immediately critical ones over the course of the hour. Armed with this foreknowledge, part 2 takes us back in time 200 years, before the lake bed was submerged, which of course piques our curiosity about what exactly caused the flood, while simultaneously revealing the ghosts' origin. It used to be that time-travel plots were rare in Doctor Who. It was used as a plot device to allow for a wide range of story settings, but almost never featured as part of the storyline. These days, that's becoming less true, to the point that time-travel is almost becoming a crutch or a cheat. But the rise in time-travel plots means that, correspondingly, at least a few will be of a noticeably higher quality, and this is one of them. I like the way that the story is set up, with part one being devoted to an exploration of the frightening aftereffects of the valley flooding, and part two investigating the circumstances that led up to that event. What's even more unexpected is that part two actually takes place in both time periods, so that we can see the future changing as the Doctor and his pseudo-companions affect the past (or, to be more accurate, as the past affects them). This allows for a really creative "ah-ha" type ending, as we learn that the flooding of the valley — an event which we'd never had cause to think of as anything other than natural — was in fact brought about by the Doctor. This development solves several mysteries from part one, like what happened to the shuttle's power cell, and why the stasis chamber was moved. And the plot features some skillful misdirection, leading us to believe that the Fisher King is inside the stasis chamber, which leads to another pleasant "ah-ha" moment when we discover the truth. This is a script that pays close attention to detail, my favorite example being when the Doctor asks whether anyone was surprised when they learned the translation of the symbols. That he ignores Lunn raising his hand is initially played off as a joke, but turns out to be a critical clue. Also, the use of Clara's hologram, which is a superb trick in itself, pays great dividends later in the story, when we learn that the Doctor's ghost is actually a hologram too, thus enabling him to essentially cheat time. Another major plus with the script is that Whithouse has incorporated some great hooks: the opening is quite creepy, with shades (har har) of The Unquiet Dead, as a ghostly Prentis and Moran advance on the base crew; and the cliffhanger, especially the dialogue, is really fantastic, as the penny slowly drops that the approaching ghost is the Doctor's.

And there are some nice references to the past, when the Doctor mentions Flesh avatars, Autons and the Nethersphere. Personally, I could've done without O'Donnell's callback to Kill the Moon, but I did enjoy what appears to be the first appearance of the season 9 arc word, with her mention of "the Minister of War". Not a title that inspires great anticipation for me, I admit, but I'm very curious to see what develops.

To be fair, there are a few plot holes. In keeping with a story of this calibre, most aren't very apparent on first viewing, but there are a couple that are fairly serious. Going through the main ones in order:

• When Moran realizes that Cass is standing right in the way of the rocket discharge, why does he simply push her out of the way, leaving himself standing literally in the line of fire? Wouldn't it make more sense, not only in terms of physics but also human instinct, for him to use his momentum to push them both out of the way? Or hurl them both to the floor, assuming that the rocket-fire would go off over their heads?

• What's the point of the ghost-luring relay race? Unless they're concerned that one of them will tire out and get caught, wouldn't it make a lot more sense to just have one person luring the ghosts into the Faraday cage? Surely that would prevent the ghosts from even thinking of splitting up. (I suppose it's just a way to hide the clever final twist from the audience, but it still seems a little bit unnecessary.)

• One also wonders, why are the ghosts willing to cut short a chase to follow someone different?

• Not so much a plot hole as a plot skepticism. The coordinates given by the Fisher King are awfully vague. From his home planet, is Earth really the only world in line with the rest of Orion's Sword? Even if we are the only one, there are far more than one forsaken town on Earth, unless the ghosts are supposed to serve as the landing lights, but if the Fisher King's people can home in on the ghosts, then it seems a bit silly that they would need to include coordinates at all. Wouldn't it make a lot more sense to just transmit the coordinates from galactic zero centre, as the Doctor usually does? I doubt it would take any more time, if Gallifrey's coordinates are typical.

• Also, does it matter that everyone is reciting the coordinates in English, when that is clearly not the Fisher King's native language? How does he expect his people to translate the directions if all the transmitters are using English? Not to mention the fact that the constellation of Orion, and his sword, only exist as viewed from Earth. The Fisher King's home planet would have entirely different constellations, and their culture might not have any concept of swords at all. Is there maybe a telepathic component too?

• A sorta-biggie: the entire reason that Prentis brought the Fisher King to Earth is that he was dead and in need of a proper disrespectful burial. Then we suddenly learn that actually, the Fisher King is totally alive. But we never get any explanation as to why that is, or how it's possible that everyone was fooled. Did he 'die' of some condition that put him in a sort of suspended animation? Was he in cahoots with the coroner and just pretending to be dead all this time?

• When the Doctor tells O'Donnell to stay behind in the TARDIS, this implies that he's trying to protect her from dying at the Fisher King's hands. Either way, this is a problem. If he genuinely believes that it's unwise to try to cheat time, then he shouldn't attempt to prevent her death. But if he really is trying to protect her, then why doesn't he tell her the full story, that Clara's list of names means that she's likely the next to die? He seems to be trying to have his cake and eat it too, which makes me think that Bennet's analysis is exactly right: the Doctor wanted confirmation of his theory, and so allowed her to be killed. (But perhaps without that confirmation, he couldn't act decisively one way or the other?)

• The Fisher King is way too tall and bulky for that little stasis chamber. How did he expect to fit inside?

• If the Fisher King's people want to drain the Earth's oceans, is it possible that they're a marine species, or at least amphibious? In which case, how can the Doctor be certain that the flood killed him?

The Fisher King, despite his peculiar name and brief screentime, is a relatively memorable monster, with his creepy resonant voice, and his impressive design, with an arching hood reminiscent of the Vervoids and icky fleshy mouth-parts protected by an exoskeleton. He certainly conveys an aura of power and menace, and comes across as a genuine threat. Peter Serafinowicz gives a lovely performance as the voice of the Fisher King, somehow managing to be naturalistic and chummy but simultaneously menacing.

Initially, the ghosts don't seem all that scary, just creepy, when it appears that they're doing little more than curiously examining people, soundlessly mouthing words at them, and occasionally hurling plastic chairs. But then we discover that the ghosts are using their limited interactive abilities to (sometimes indirectly) murder people, in order to increase their numbers, and that makes them scary. I really like that the ghosts follow consistent logical rules, even if we don't always know how or why those rules work. The explanation for why the ghosts don't always kill people — if you haven't been 'infected' by the earworm, they aren't interested in you — makes perfect sense. Monsters are always most effective when they have clearly-delineated strengths and limitations, and the ghosts' ability to only interact with objects made of metal — like knives or harpoons or, in one clever twist, Clara's phone — helps to drive the plot in interesting ways, along with enabling the audience to think ahead and consider methods of attack that the ghosts might use, which increases the tension. This leads to great scenes like Moran's ghost — either unable or uninclined to lift heavy weights for a long period of time — stalking after Cass while dragging a metal axe across the floor in a very casual-serial-killer way. And even when they're not in a murderous mood, the image of them speaking soundlessly is quite effective. Their design is also unsettling, with those big soulless black eyes making even the nicest of characters seem menacing in death.

Even though the guest characters are, to be perfectly honest, rather one-dimensional, I really liked them all. They're only characterized with the broadest of sketches, and yet we hear enough little details about each person, and they're brought to life so vividly by the actors, that we become invested in their survival. I also appreciate that there's at least an effort made to give each of the crewmembers their own unique talent, which enables them to contribute to the developing plot in specific ways. In an unlikely twist, all of the four main guest characters are secretly in love with one another (not a four-way poly relationship, I hasten to clarify, but rather two pairs of lovebirds), yet it does manage to seem sweet rather than saccharine and manipulative.

Cass — the natural leader — immediately caught my attention because, to my great delight, she's Doctor Who first Deaf character who communicates through sign language. This feels like a long time coming, although I do understand the omission up to this point — I'm sure that many hearing writers aren't knowledgeable about how to write naturalistically for Deaf characters, and it does present certain challenges, like the need in this episode for Lunn to translate everything Cass says — but in some ways that makes for a much more authentic group dynamic, because this is how people really do interact in the real world. And even though Whithouse provides Lunn as a mouthpiece for Cass' thoughts, Cass illustrates quite well that a character doesn't need to vocalize the dialogue in order to play a full part in the narrative. I was thrilled just to see a Deaf character on Doctor Who, but I was even more excited that the episode goes to some lengths to help us understand how Cass interacts with the world, so that instead of viewing her deafness as a disability, the audience gains an appreciation for Cass' differing strengths, and how her way of viewing the world gives her an advantage that no-one else in the crew possesses. I absolutely love the way that Cass' skill at interpreting vibrations is used. Not only is she smart enough to decipher what she's feeling, she can also make use of that information to dodge Moran's attack. It's a wonderful scene that transforms her from "obvious vulnerable target" to "perceptive, agile smartypants", and — even though she doesn't go on the offensive — gives her a great deal of agency in the storyline. Not that Cass has lacked agency up to this point; in fact, she's one of the crew's most talented members — she's decisive, wise, and analytical — and evidently also the most intelligent, given that the Doctor tells her "Whenever I step outside, you are the smartest person in the room." Most delightfully, Cass is able to lip-read what the ghosts are saying, a skill that no-one else has, although you know that the Doctor would've sprouted that ability if Cass hadn't been around (which is an excellent illustration of why it's best to understand your characters' limits, and introduce other characters who can help in those specific areas, rather than making your hero all-powerful). It's portrayed realistically, too, because Cass doesn't always interpret the ghosts correctly the first time. Even though she's mainly required to portray anger and stubbornness, Sophie Stone gives a wonderful performance, which really illustrates the emotive richness of sign language (as Clara observes, "Didn't need anyone to translate that..."). Her look of terror when Cass spots Moran's ghost for the first time is spine-tingling, and it's lovely to see her smile at the end — a rare moment of levity and happiness for her character — after Cass kisses Lunn.

Alice O'Donnell — the Doctor Who fan — really comes into her own in episode 2, when she and Bennet become the Doctor's pseudo-companions, although in her case, this is more due to Morven Christie's infusion of infectious enthusiasm and stubbornness rather than any character details. It's so cute to see her geeking out over meeting the Doctor, just as any of us would. Presumably she and Osgood are having a fantastic time together in Doctor Who Beloved Guest Character Heaven. I was really starting to like O'Donnell, so I was gutted when she was killed off. Fun delivery of "It was nothing.", "Who wants to live forever anyway?", "One small step for man, one giant hwuuuuu...", and her cries of pain are horribly realistic.

Bennet — the cowardly one — is engagingly relatable, as he repeatedly puts himself in harm's way despite a deep reluctance to do so, and a complete lack of faith in his ability to hold his own in a fight. His character, too, gets greater depth in part two, as we learn that behind his nervous exterior, he's insightful and even a bit cynical. Loved Arsher Ali's nervous "Hey, how's it going?" to get the ghosts' attention, and "But they're ghosts, though."

Cass' signer, Tim Lunn, is given so very little backstory and characterization that I couldn't even come up with a two-word description for him, but Zaqi Ismail imbues him with such personality that it feels like we know more about him than we really do. Given the tragic end of O'Donnell and Bennet's relationship, I find I can overlook the slightly schmaltzy beginning of Cass and Lunn's. I'm a sucker for an eventually-requited love story, and my heart melts a little when Cass pulls Lunn into a passionate kiss. Great delivery of "The other, er, the moley guy, we don't know who he is."

The delightfully-named Richard Pritchard — the untrustworthy capitalist — is brought to vivid life by Steven Robertson, who gives an absolutely pitch-perfect performance. His delivery is heightened enough to make it abundantly clear that Pritchard is only interested in the bottom line, but it never crosses into satire. Even though he's clearly meant to be the unlikeable one of the bunch, Pritchard was so unscrupulously self-interested, and Robertson's performance so entertaining, that I was actually kind of sad to see the character die so early in the story.

In much the same way, Paul Kaye gives a highly entertaining performance as Albar Prentis, an almost creepily obsequious character whose efforts to tempt other people into enslaving him almost come off as sexualized flirting! (Witness his breathy delivery of "At the risk of starting a bidding war, you could enslave me.") It's nice to see a Tivolian again! Kaye has a wonderful laugh, and I loved his delivery of pretty much every line, especially "He and his armies invaded Tivoli and enslaved us for ten glorious years! — until we were liberated by the Arcateenians. But, thank the gods, soon we'd irritated them so much, they enslaved us too! Ha ha!"

Captain Jonathan Moran (Colin McFarlane) — the skeptic — is dead before the end of the teaser, so his character doesn't much register, but his ghost does have a funny moment of disappointment when his fist-through-the-heart doesn't work.

This is a strong story for the Doctor, who spends the episode systematically investigating the mystery of the ghosts, and peeling it back layer by layer. His wide-eyed wonder (one might say "geeking out") at the possibility of ghosts is pretty cute. Alongside his general arc of deduction and detection, his character is developed through lots of little details, not least of which is the revelation that Clara has resorted to preparing him a set of flashcards to use when dealing with distraught people. I really appreciate that the Doctor knows (or, at least, used to know) sign language, which leads to the interesting revelation that the Doctor's skillset can be rearranged or deleted with each regeneration. Thinking about it, it seems blindingly obvious (since, for example, some Doctors revel in their musical abilities whereas others never display such talents) but I've never really thought about the possibility that he might lose a critical skill rather than just character details. We get a glimpse of darkness, too, when the Doctor practically guilt-trips all the crewmembers into staying, which is really rather questionable ethically. That old "the Doctor is going to die!" plot thread rears its head yet again, but for some reason, this time I don't mind it, maybe because it works so well with the time-travel element of the plotline. And maybe this repetition is deliberate, and they're building toward something? Perhaps related to the Minister of War? Time will tell. Loved Capaldi's delivery of "Hello! Did you want to show us this? It's very nice.", "It's okay, I understand. You're an idiot.", "Why can you only handle metal objects? Oh, I didn't know I'd noticed that.", "A bit murdery, sure, but even so!", "Calm, Doctor. Calm. You were like this when you met Shirley Bassey!" which made me LOL, his very Fenricesque "O'Donnell, excellent work returning the base to day mode!", "You trust me, don't you, Clara?", "Yet.", his snappish impatience on "Give it to me now, I'm gonna take the batteries out.", and "Even the tiniest change could be catastrophic."

In their second outing, his sonic sunglasses serve an absolutely tailor-made purpose, as he uses them to interface with the crew's visual cortex and erase any memory of the alien symbols. But even more than his sonic sunglasses (since I'm still on the fence about them — although I certainly don't hate them as much as some people apparently do!), I was delighted to see the Doctor's electric guitar make a reappearance, and in such an appropriate way — well, not that Beethoven really has anything to do with the episode, beyond belling the cat with regard to the episode's central paradox, but it's still thematically appropriate. The icing on the cake, though — or maybe the cherry on the icing on the cake that I've been coveting all this time — is that the electric guitar bleeds over into the theme music! I've been feeling that the theme music, while cool, lacked punch, and it turns out that electric guitar is exactly what this theme needed. It now echoes into the start of the episode as the theme fades away, which is just awesome. It's such a perfect fit with both the current theme music and Capaldi's Doctor that you'd think they planned its inclusion all along. Regardless, I really really loved it and I really really hope it sticks around for the long run.

Clara, frustratingly, is coming off as a generic companion again — her sudden thirst for adventure and inappropriate glee at the idea of a tragedy having befallen the crew are reminiscent of Tennant-era Rose, and it makes you wonder what on earth Clara's been doing lately (or not doing!) to give her such a sudden yearning for mayhem. I also found myself rolling my eyes at her refusal, yet again, to allow the Doctor to even consider dying. Death is never fair, and Clara should understand that as well as anyone. Worse, her motivation for refusing to give up hope comes across as a bit selfish: "You do not leave me!" However, I must be quick to praise her character-specific moments, like the very hilarious teacher-y flashcards that she's written up for the Doctor, to prompt him to give appropriately empathetic responses to people's concern or distress, and her realization that Bennet was in love with O'Donnell (even if her advice to him is yawnsomely trite), triggered of course by echoes of her own loss with Danny. I'm also amused by how very easy it is to envision her argument with Gandhi that the Doctor references. (Yet another interesting missed adventure!) So while much of her material may be relatively generic, there is a theme running through many of these scenes, in that Clara is getting bolder and perhaps a bit stroppy. This fits well with her response when Cass accuses her of being cold-hearted. Clara's defense — that the Doctor has taught her to do what needs to be done — is a nice answer, I think, and demonstrates that Clara at least believes that she's becoming more hard-edged. (I'm not sure if this is actually true; Kill the Moon comes to mind again.) On a less important topic, I am not a person who wears yellow, and I suspect (thanks to my mother's devotion to Color Me Beautiful back in the '80s) that Clara doesn't have the skin tone for it either, but despite myself, I really like her mustard-colored outfit. Great delivery of "Okay, they now appear to be arming themselves.", "I know, and I appreciated it.", "I'm beginning to think we should've let the ghosts in on the plan.", her little nod of assent for O'Donnell to open the door, "No." when the Doctor asks if he's saying the same thing as the others, and the cute scene of her whispering to get Cass' attention until she realizes how futile that is.

I was very impressed with first-time Doctor Who director Daniel O'Hara, whose direction really enhances the look of both episodes. He handles the Fisher King particularly well, keeping him hidden in shadows until his effective reveal. (Kudos to the lighting team, too. Not only is the Fisher King lit really well in general, but there are also some great backlit shots of the Doctor and the Fisher King in silhouette. Their work also adds great atmosphere to scenes in the underwater base, with its shadowy corridors accentuated by light reflecting off the rippling water.) His decision to indicate the symbols' mystical power through visual effects is absolutely brilliant: when we see them on the wall, the symbols are just ordinary carvings, but when we see them reflected in someone's eyes, they blaze with bright white light, as if they're burning themselves into their victim's retina. It's a directorial choice that merely seems artsy at first, but takes on greater significance once we understand the function of the symbols. The only thing I would've changed, maybe, is the scene of Cass being stalked by an axe-wielding Moran: every time I watch it, I wish that the shots of Cass had been utterly silent, so that we couldn't hear Moran's approach either. But it's a very minor suggestion in an excellent episode. Among his other great shots: the creepy (possibly inadvertent!) shot of Pritchard looking at Moran's ghost (because of his reflection, it almost looks like another ghost has appeared behind him); the excellent direction indicating that Moran's ghost is leaving Lunn alone; the dramatic shot of the Doctor and Clara chatting across a hallway, as water fills up the corridor between them; the handheld camera work for the footage from Clara's phone; a pretty decent dolly zoom as the Fisher King roars in the distance; O'Donnell, through a cracked pane of glass, hiding from the Fisher King; and the shot of Lunn being surrounded by five ghosts.

I have much praise for the set designers, too, who have created a very believable underwater base, with claustrophobic curved mildewy corridors. My favorite touch: the disturbing kraken mural on the dining-room wall (who wants to look at that while they eat?!) which, as it turns out, bears a passing resemblance to the Fisher King. The design of the spaceship is nice, too, with its pristine interior and nacelles housing pointy star-shaped engines.

In the realm of effects, there's a great model/CGI establishing shot of the base at the episode's start, with its lights struggling to penetrate the murky water that likewise obscures its details from view. The semitransparent ghosts look wonderful, too, especially the way they distort what can be seen through them, and the way they look as though they're sloughing off energy, or radiating it, as they move. And I love the dramatic footage of the base flooding.

Murray Gold contributes a good score, especially the music as the ghosts inspect the Doctor and Clara, during the chase sequence, and as the base begins to flood. Some of the sound effects are especially good, too, like the buzzing, creaking, screaming noise as the ghosts analyze Lunn, and the very freaky noise of Moran's ghost dragging the axe along the corridor floor.

It didn't even occur to me that we had no Shut-Up Counter last week. Good work, Mr Moffat, and thank you! This week, the counter returns, but with only a single rather cute example:

SHUT-UP COUNTER: 1 1.   (24:04)   Doctor: "O'Donnell, excellent work returning the base to day mode!" O'Donnell: (embarrassed) "Shut up, it was nothing."

My review schedule has been thrown into complete chaos by the fact that I'm currently on a two-week trip overseas. Finding time to watch Doctor Who isn't a big problem, but finding time to review and take notes is. If only a complete two-parter had aired while I was gone, it wouldn't have been so bad, but instead I saw Under the Lake before I left, so now I have to take notes on, and review, a two-parter in the middle of my trip, and then follow it up with another single episode that I somehow need to finish before I fly home, because Gray's coming to visit me the day after I return and I feel sure he's going to want to watch some new Who together, so I have to get caught up. I was able to download Before the Flood while I was in Doha, and watched it not long after, but I've been so solidly busy from morning until bedtime that there hasn't been a spare moment to even think about this review. But I finally carved out a few hours here and there for note-taking and I'm currently attempting to type my first draft on a train from Jaffna to Colombo, with a dying laptop (no power outlets on the train, you see), and a track that bounces so much that you're frequently lifted off your seat. Not, shall we say, optimal conditions! — Ultimately, between the time pressure during the trip, and the lack of solo reviewing time while Gray's staying with me, it's taken me until October 31 to finish this. So now I'm really behind; thank goodness the next two episodes appear to be a two-parter after all. That's my only hope for getting caught up to the newly-airing episodes!

Minor points:

• Toby Whithouse definitely has a gift for dialogue, and this two-parter is full of entertaining lines. He gets us started right off the bat with:

  Bennet: "I've not seen technology like this —"
  Moran: "Please don't say 'on Earth'."
  Bennet: "...on Earth before."

• Is it just me, or does the ship attacking the kraken appear to be crewed by Kirk, Spock (or McCoy) and Scotty?

• I find myself skeptical that comprehension of BSL — assuming that's the dialect Cass speaks — would be a deletable skill in the regeneration lottery. Isn't that something the TARDIS translation circuits should handle? Even though, in this case, it clearly doesn't, since Clara can't understand her either. (Still, I don't think this is necessarily a bad thing; requiring a translator for Cass opens up some interesting dramatic and dialogue possibilities, and it's also a more respectful option than dubbing a TARDIS-generated voiceover onto her signing. Anyway, Lunn's presence is kind of obligatory because Cass would still need to be able to communicate with the other crewmembers.)

• I love that Clara can say this with a smile:

  O'Donnell: "Oh, it's all right, they only come out at night."
  Clara: "Weird how that's not comforting."

• Beautiful delivery by Robertson, who barely skips a beat:

  Pritchard: "I imagine they're pretty valuable?"
  Doctor: "What?"
  Pritchard: "I mean, powerful. Those power cells, I imagine they're pretty powerful."

• Is it really possible that the Doctor has never met a ghost? I would've sworn there had been at least one. The TARDIS Data Core, however, says no, and I trust them!

• Pritchard's death is one of those wonderful "I can predict exactly what's about to happen to him" moments... as soon as he takes off his helmet, you just know he's done for, and how. That was really not a wise move, Pritchard. In fact, while we're on the topic, I also question his judgment as a ghost. So many metal objects he could pick up, and he chooses... a plastic chair? I mean, it would be painful to get whacked upside the head with one, but I don't exactly see it as a deadly weapon.

• Why does the base stop automatically checking the flood locks at night? Isn't that the time of day when they should have the most security, since there will be fewer people awake to tackle developing problems?

• With ghosts hot on his heels, why does Lunn stand in the middle of the doorway, waiting for the door to close? Shouldn't he at least try pressing himself up against the wall, like Clara does, to make himself a bit less obvious?

• Why does the Doctor stop Cass from going to rescue Lunn? Presumably he assumes it's futile and she'll get herself killed, but he would never let anyone stop him from going to Clara's rescue.

• Why does Lunn cower ineffectually from Pritchard's ghost, rather than, say, running through him? It's not like the ghost actually has him cornered. Except, of course, that Lunn is trapped in a confined space; so why doesn't O'Donnell immediately re-open the flood door so that he has a chance at escaping?

• I'm rather shocked that nobody but Cass was wondering what "the temple" was. I'd been waiting so long for him to explain the fourth part of the directions that I actually forgot I was still waiting! (Still, I appreciate that he poses a question to which it's actually conceivable that we might have figured out the correct answer! Too often these kinds of questions have answers that we never could have guessed, much less deduced, so this makes a very welcome change of pace. Plus it makes us feel really good about ourselves if we did guess what the fourth question was.)

• A Buffy-worthy line, made all the better by Jenna Coleman's matter-of-fact delivery, as if this is a perfectly natural thing for the Doctor to have done. (And, poor Doctor; how did he wind up waking up to the same song every day for two weeks? He must listen to a terribly predictable radio station.)

  Doctor: "Clara, why don't I have a radio in the TARDIS?"
  Clara: "You took it apart and used the pieces to make a clockwork squirrel."

• I guess every story has to have at least one dialogue stumble. For me, this line is trying way too hard.

  Doctor: "It's impossible, I hate it, it's evil, it's astonishing. I want to kiss it to death."

• O'Donnell, honey, don't you think it would be better to hit the "activate" button on the timer after you've informed the others that "we've got 30 seconds"?

• When the Doctor tries to communicate with Clara over the intercom, she unhesitatingly hits the correct button(s) to activate the connection. But how on earth does she know what to press? Has she been to this time period before? (Plus, the button she presses appears to be the letter "J" — unlike the Doctor, who seems to press the space bar. I am unclear on the link between the letter J and activating an intercom. J for... jabber?)

• It is perhaps a nice little clue that the Doctor's 'ghost' appears immediately after their departure, but O'Donnell's ghost doesn't appear until the moment she's killed.

• I didn't notice this until my third viewing, but the Doctor's bust of Beethoven has Capaldi eyebrows!

• Delicious.

  Doctor: "This is called the bootstrap paradox. Google it."

• Despite the name, Before the Flood turns out not to be a sequel to The Waters of Mars.

• Cute line, which gives O'Donnell some nice backstory. I must say, this is not something I would have expected of her!

  O'Donnell: "I was demoted, for dangling a colleague out of a window."
  Doctor: "In anger?"
  O'Donnell: "Is there another way to dangle someone out of a window?"

• An example of twenty-first century humor that actually works!

  Prentis: "Our capital city has a sign saying 'If you occupied us, you'd be home by now.' "

• Right after loudly declaring that they mustn't do anything to change history, the Doctor threatens to remove the batteries from the hypothetical device that creates the ghosts. But, um, that would be really changing history.

• Stupidest dialogue that characters being chased by monsters should never ever say:

  O'Donnell: "Well, split up!"

• The Fisher King appears to clomp around quite heavily, so how is it that he sneaks up behind O'Donnell without her hearing a single heavy footfall? (And why on earth does she turn her back on the door when she knows he's in the vicinity? AND why does she just stand there gawping when he aims his weapon at her???)

• Really, really nicely written. I love how the TARDIS is like "um, no."

  Doctor: "I'm gonna go back to the base and I'm gonna save Clara, because that's what I do, and I don't see anyone here who's gonna stop me."
  The TARDIS rematerializes.

• When the Doctor tackles Bennet, it makes a huge crash that even catches O'Donnell's attention. But after three viewings, I constantly missed the moment of the crash from the perspective of the original timeline. Finally, on my third viewing, I rewound to track it down, and discovered that the noise is barely noticeable at all.

• I wonder what makes the Fisher King so confident that the Doctor will sacrifice himself, rather than change the future? He doesn't know that the Doctor thinks his death has been predicted.

• When the ghosts converge on Clara, Cass and Lunn in the dining hall, we get a good shot of 9 slices of pizza (along with what appear to be meatballs and marinara sauce) sitting under the heat lamps. Those slices of pizza have, I suspect, been there for a very long time. After all, two of the same pizza slices are featured prominently in the scene of Clara and Bennet chatting in the kitchen, just after Pritchard dies, at 20:03. The implication is that they were put under the heat lamp the day before, at the very most recent, so they surely must be getting pretty crusty. And as for those meatballs — if they actually are meatballs, and not undercooked gulab jamun or something — I'm not even sure they'd still be safe to eat (unless those are futuristic food-safety heat lamps?).

• Somehow, this story takes all my "don't do this" pet peeves and makes them work. The "please stow any hand luggage" joke is actually pretty cute, because even though the humor is firmly rooted in twentieth-century Earth life, it's coming from the Doctor, rather than the TARDIS, who — along with Bennet (presumably) — is familiar with that cultural reference.

• From the time the stasis chamber first activates, at 26:15 in part 2, until 32:43, the display drops from roughly thirteen red bars down to one, which implies that the chamber's occupant is about to awaken. But the next time we see the chamber, at 35:47, its display is suddenly full again. What gives?

• Had the Fisher King just been a bit more of a quick thinker, I bet he could have scurried into his shuttle before the flood hit, and flown it to dry land. (Unless he doesn't know how to pilot Arcateenian crafts?)

• The Doctor's initial theory was that the ghosts were dormant during the day because of the security sweeps being automatically run by the base. But now he's decided that "they're electromagnetic projections that were out of phase with the base's day mode", whatever that means. So, nothing to do with the security sweep then?

• Eep!

  Doctor: "You might find you've lost a couple of other memories, too, you know, like people you went to school with, or previous addresses, or how to drink liquids."

Even though two-parters feel unusually long these days, I must admit that I've really missed storylines that give the material a chance to breathe, and the characters and settings more time to develop. Given how successful Under the Lake / Before the Flood is on those counts, I'm feeling really optimistic about the rest of this season, with its much higher percentage of two-parters. If they're all up to the quality of this one, with equally good monsters and minimal padding, then we may have some real treats in store.