At the ticket hall of Piccadilly station, the group rejoins with Travers and Victoria. Chorley and Arnold appear and Arnold is revealed to be the traitor, having been killed and his corpse reanimated as a vessel for the Intelligence. The Doctor appears to submit to the Intelligence and places himself inside a pyramid-shaped machine that the Intelligence intends to use to drain his mind. Just as the Doctor is apparently about to have his mind drained, Jamie calls out to the servile Yeti to attack Arnold; Jamie, Anne and Professor Travers try to drag the Doctor from the machine against his wishes. After Jamie rips its wiring out, the pyramid explodes and the Yeti and Arnold fall to the floor, lifeless without the influence of the Great Intelligence, which has now been dispersed back into space. Everyone is happy except for the Doctor. He explains that he had sabotaged the conversion headset and would have drained the Intelligence had the device been used – but now the Intelligence is free once more. After saying goodbye, the Doctor, Jamie and Victoria slip away and head back to the TARDIS.