(BARBARA points to the scanner where the picture has changed to that of a swampland accompanied by the cries of strange creatures.) (SUSAN holds onto the DOCTOR'S shoulders, whilst the DOCTOR looks pointedly at IAN and BARBARA, then cautiously reaches towards the scanner switch. (The DOCTOR feels the back of his neck.) All right. As he hurries round the console, there is an explosion and everyone is knocked to one side and the room is plunged into darkness. BARBARA: No it isn't, but does it have to be? BARBARA: The ship! BARBARA: They must have been forced open. CONSOLE ROOM
(The DOCTOR enters from the living quarters and walks over to the control panel. DOCTOR: Susan. He giggles and leaves.) IAN and BARBARA cross over to her.) IAN: (Slowly.) TARDIS. That's can't be what's outside the ship. The DOCTOR is lying on the floor beside the console. The TARDIS doors are wide open. The TARDIS! What for? When he comes near them, they close on their own accord.
Plan: A: the TARDIS floor; Q: Where were the Doctor, Susan, Ian and Barbara thrown to? A: Susan; Q: Who is the Doctor's companion who is acting strangely? A: suspicions; Q: What is raised that an alien force may have entered the ship? A: The Doctor; Q: Who accuses Ian and Barbara of sabotage? A: the travellers; Q: Who realizes that the TARDIS is trying to warn them of something? A: an attempt; Q: What does the TARDIS itself reveal to be happening to warn them of something? A: time; Q: The Doctor realizes that the fast return switch he used when leaving Skaro has stuck, and the ship has been plunging back to the beginning of what? A: its own destruction; Q: What does the TARDIS go back to the beginning of time to see? A: a faulty spring; Q: What is the problem with the fast return switch? A: his behaviour; Q: What does the Doctor apologize for? Summary: As they slowly recover from the shock of being thrown to the TARDIS floor,the Doctor, Susan, Ian and Barbara all seem to be acting strangely. Unexplained events occur and suspicions are raised that an alien force may have entered the ship. The Doctor even accuses Ian and Barbara of sabotage. It gradually dawns on the travellers that what they have been experiencing is an attempt by the TARDIS itself to warn them of something. The Doctor finally realises the fast return switch he used when leaving Skaro has stuck, and the ship has been plunging back to the beginning of time and its own destruction. Once the problem - a faulty spring - is corrected, the TARDIS returns to normal and the Doctor has to make some apologies for his behaviour.