Parts: 2 (45-minute)
Writer: Matthew Graham
Airdate: 21 — 28 May 2011
Production Code: n/a

Doctor: eleventh
Companions: Amy, Rory

Creature Feature: the Flesh

Story: On an isolated island off the British coastline, a crumbling medieval monastery houses a futuristic acid refinery, from which boiling acid is transported through reinforced piping to the mainland. Processing the highly-corrosive acid is dangerous, deadly work, and the high mortality rate of the plant workers has led the company, Morpeth Jetsan, to devise a clever solution: the Flesh. A glossy white liquid, the Flesh can reform itself into any shape desired, and — when animated by a downloaded human consciousness — can even become a living, breathing dopplegänger for the human workers, able to carry out dangerous tasks with no risk to its human operator.

The TARDIS crew arrive on the island just in advance of a solar storm, which threatens to cripple the plant and its acid containment systems. The crew stubbornly refuse to evacuate or shut the plant down, and when the storm wave strikes, the energy it releases creates an even bigger problem: the dopplegängers — called "gangers" — have stabilized independently of their operators, identical duplicates with all the memories of the originals. Now the Doctor must stop fear and suspicion from destroying humans and gangers alike...