The TARDIS arrives in the hotel. The Doctor, Amy and Rory exit and begin to look around them. The Doctor says that it is clearly alien and is fascinated by the fact that aliens would want to imitate such a thing. Rory finds a collection of photographs on the wall. They depict a mixture of humans and aliens and each has the name of a subject and a caption. The captions are incomprehensible:"Balloons", "Plymouth", "that brutal gorilla". They ring the bell on the reception desk and are immediately confronted by two humans, Rita and Howie. Behind them is Gibbis, a mole-like alien from Tivoli, the most invaded planet in the galaxy (a fact that he seems curiously proud of).
Rita is quick to realise that the newcomers are just as surprised as they are and are either no threat or something new to be learned from. The Doctor is impressed by her and jokes that Amy is fired as his companion. Howie tells them that there is no way out and all the exit doors are walls. There are no windows either. Rita adds that the corridors and rooms are constantly shifting and that each room contains 'a bad dream'. The three of them tell how they were snatched from their lives two days earlier and found themselves in the hotel.
The Doctor leads them back to where he left the TARDIS but it is gone. He asks if there are any more people there and Rita tells them that Joe is "tied up right now." They take the Doctor to a bar area where Joe is tied to a chair amongst a large number of ventriloquist's dummies. Joe tells him that he used to be scared of dummies but now he finds them amusing. He adds that everyone has their own room. He talks cryptically about being too raw when he arrived but says that he is now "cooked" (the Doctor's word) and that 'He' shall feast. The Doctor attaches Joe's chair to a trolley and the group begin to search for the TARDIS or, failing that, an exit.
On their way, Howie opens the door to a room despite the Doctor's attempt to stop him. Inside are five attractive girls who make fun of his stammer and his ability to speak Klingon. The Doctor pulls him away and reassures him that Howie is right; it is all a CIA plot. As they go down the corridor, Howie mutters "Praise him," and a low growl is heard.
The Doctor spots a place in the ceiling which seems to have been gouged away and Amy picks up some papers from the floor nearby. A roar is heard. As the Doctor hurries them away to hide, Rory sees a fire exit but when he looks again it is a hotel room door. The group dash into two rooms. Rita finds herself with Joe and her domineering father, admonishing her for getting a B grade in maths. She apologises and then says "Praise him." In the other room where the other five are hiding stand two weeping angels. The Doctor realises that they are holograms. He thinks that they are Amy's bad dream but Rory says that they are meant for someone else.
Joe's ropes slide off his arms and he runs off. The Doctor peeps through the spy hole in the door and sees an alien Minotaur pass down the corridor. When he dashes out after it he sees Joe being dragged down the corridor. He follows but the corridors distend and shift. When he finds Joe, it is too late; the man is dead.
Back in the bar, Amy tries to cheer up Gibbis by telling him that the Doctor will save them all. The Doctor and Rita talk. She says that the Doctor's idea of being on an alien planet is no more far-fetched than her own theory that they are in the Muslim hell. They ponder how Joe died and the Doctor says that the man's spark went out as though his faiths and fears vanished. Watching from a distance, Rory tells Amy that when he sees the Doctor getting friendly with anyone he has the urge to phone their next of kin. Amy remembers the paper she found and gives them to the Doctor. They are Lucy Hayward's last writings. As the Doctor reads them, Howie blurts out, "Praise him!"
Gibbis says that this is what happened to Joe. He thinks they should just give Howie to the creature. The Doctor says that they will all stick together. He takes Gibbis aside and berates him for his aggressive cowardice and promises that no-one else will die. He then says to Howie that when he is next possessed by the creature he will ask some questions. Howie confirms, in his possessed state, that he wants to be eaten. The Doctor tells the others that he is going to capture the creature.
He has Gibbis guard Howie in reception and uses Howie's voice, broadcast over the hotel PA system to a room upstairs, to lure the beast. The Doctor talks to the Minotaur and finds that the hotel is a prison and that the victims are the Minotaur's "lunch.' The creature tells him that they are not ripe. It adds that they have to be made ready and then says that it has been there so long it has forgotten even its own name. The Doctor realises that the creature wants all of this to stop. Before they can go on, Howie appears on the stairs below; he has persuaded Gibbis to let him go. The Minotaur breaks out of the room and goes to kill him. It knocks Rory down on the way. As Rita tends him and the Doctor runs after Howie, Amy finds her room.
She opens the door but Rita steps in front of her before she can go in and Amy sees nothing. The Doctor finds Howie's corpse as Gibbis appears, trying to say that Howie overpowered him. The Doctor and Rory make their way back to the photographs on the wall: Howie's picture is already there.
Rita pulls the Doctor aside and asks why he feels the need to save everybody all of the time. She says that it sounds like he has some sort of God complex. He says that he feels responsible to Amy and Rory: if he offers everyone all of time and space he shouldn't be surprised that they take it. The responsibility for their safety is therefore his. he offers to show Rita all of time and space, too, when they escape from the hotel. He notices a CCTV camera and rushes off, saying "Got you, Mr Minotaur." Rita looks into the camera and says "Praise him." The Doctor passes room number eleven and opens the door. He hears the TARDIS cloister bell and looks inside. He says, "Of course. Well, who else?" He smiles before shutting the door gently.
He finds the surveillance camera room from which he sees Rita making her way through the corridors. He calls her on the phone of a room she is passing. She answers and apologizes on the phone to the Doctor. She asks that he doesn't watch her being robbed of her faith but says that she can feel the rapture approaching and feels blessed. Amy and Rory arrive behind the Doctor but he switches off the screens as the Minotaur's shadow passes in front of Rita.
After Rita's body is laid on a stage in the bar beside those of Joe and Howie, the Doctor is full of rage, smashing objects and screaming. It is then that he realises that the Minotaur is not feeding on people's fear but their faith. Rita had religious faith, Joe had faith in conspiracies and Joe was a gambler who believed in luck. It is only when people fall back on their faith that they begin to offer praise. Rory has been unaffected, even shown exits, because he has no strong faith in anything. Amy, on the other hand, has faith in the Doctor. At this moment she says, "Praise him,"
The four survivors run through the corridor, pursued by the Minotaur. Amy stops to face the creature but they drag her in to a room. It is hers, and little Amelia is inside, sitting on her suitcase. Amy's greatest fear is revealed: waiting for the Doctor.
The Doctor tries to break Amy's faith in him. He tells her that this is how it ends for his companions; those who come with him die or get hurt. He says he is not a hero, but a mad man in a box and it was vanity that made him come back for her. He calls her Amy Williams. With Amy's faith in him broken, the Minotaur begins to die. The hotel architecture vanishes to reveal itself as a deck on a space ship. The Doctor accesses the ship's systems and finds that the Minotaur is of a species related to the Nimon. They visit worlds and set themselves up as gods but when the people become secular the Minotaurs are imprisoned. The creature was fed by scooping up people with strong faiths, keeping it alive beyond its desire to live. The ship's systems have failed, he says, and the fears of the previous victims have been left behind.
The Minotaur talks to the Doctor about "An ancient creature drenched in the blood of the innocent, drifting in space through an endless shifting maze. For such a creature, death would be a gift." When the Doctor tells the Minotaur to accept death it says, "I wasn't talking about myself." It dies.
The Doctor drops off Gibbis and takes Rory and Amy back to Earth. He lands outside a house and gives them the keys. Outside is Rory's dream car, a goodbye present. Amy asks Rory to leave them for a moment so that she can ask the Doctor why he is abandoning them. He says that he can't keep putting them in danger and doesn't want things to end with him standing by their graves. Amy tells him that, next time he sees River, he should get her to visit "her old mum." The Doctor enters the TARDIS and it dematerialises as Rory re-emerges from the house. He asks what the Doctor is doing and Amy tells him that the Doctor is saving them.
On board the TARDIS, the Doctor stands alone, looking aghast.