God Complex

A prison ship was built to hold and feed a captured Minotaur.

Features
The interior of the prison ship modified itself to take advantage of the fear of its subjects, creating rooms holding their worst fears. The entrances would be blocked off and the interior would warp in on itself to get people lost. The ship could also transport people of great faith into itself. (TV: The God Complex)

History
A civilisation captured a Minotaur which was masquerading as a god. They built the ship to contain it and set up the system to feed it faith. People would be shown their fears and rely on their faith to fight it. The Minotaur would replace the faith in whatever they believed with a faith in the Minotaur. The Minotaur would then feed on this faith, killing the subject.

Over time, the ship started to break down and developed a glitch. It was trapped in the shape of a 1980s Earth hotel and the rooms of the previous victims remained after their deaths. Also pictures of the victims would appear on the walls, most of them (even non-humans) would be dressed in white shirts and red ties. The Minotaur lost its will to live and wished to die, but the ship continued to feed it and it lacked the will to commit suicide.

The ship had captured faithful people from across time and space, creating rooms to prey on their fear. These included Commander Halke, who was afraid of defeat; Paige Barnes, who was afraid of other people's socks; Novice Prin, who was afraid of sabrewolves; Lady Silver Tear, who was afraid of Daleks; Royston Luke Gold, who was afraid of Plymouth; Tim Heath, who was afraid of having his picture taken and Tim Nelson, who was afraid of balloons, as well as a Silurian, a Judoon, a Tritovore and a Hoix. Two other rooms had a PE teacher and a clown.

One group of people was brought in and killed. Luke was the first of the group to die. Lucy Hayward was the last survivor. She became a victim of the Minotaur after seeing a gorilla she saw in a book. The next group consisted of Joe Buchanan, Howie Spragg, Rita and Gibbis. The Eleventh Doctor, Amy Pond and Rory Williams were brought to the ship two days later. The Doctor, not knowing what they were facing, told them to fight their fears, which only made them more vulnerable. Joe, who was afraid of ventriloquist dummies, was the first to be targeted and killed; while trying to avoid the Minotaur and save Joe, Howie, Rita and Gibbis were all possessed; Howie after finding a room where he was ridiculed for his stutters, Rita when she saw her father in one of the rooms and Gibbis after finding a room with a Weeping Angel inside. When Howie was targeted, the Doctor tried to save him and contact the Minotaur, but Gibbis let Howie go to try to save himself and Howie was killed. Amy and the Doctor were both possessed soon after; Amy after seeing a room containing her childhood self shortly after the Doctor abandoned her, (TV: The God Complex) and the Doctor after seeing the cracks in time and space he thought had been closed in his room. (TV: The Time of the Doctor) Rory was unique in that he had no overwhelming fear or fundamental faith; he was a victim of proximity to Amy and the Doctor, and as a result, the "hotel" kept showing him emergency exit doors which only he could see.

When Rita realised she was next, she separated herself from the others and gave herself to the Minotaur. When Amy was targeted, the Doctor finally figured out what the Minotaur fed on. He saved her by showing that her faith in him was misplaced, depriving the Minotaur of its food and allowing it to die. The ship shut down shortly after. By going through the ship's in-flight recorder, the Doctor was able to figure out its history and the history of the Minotaur. (TV: The God Complex)

Behind the scenes
The prison is not directly referred to as a spaceship or a prison ship in dialogue, only as a "prison". The closest the episode comes is when Rory mentions after noticing he's in space when he looks outside a window, that the people that imprisoned the Minotaur built "prisons in space", and the Eleventh Doctor describes the prison as "all automated" and "drift[ing] through space".