Doctor Who: 10 Biggest Lies The Doctor Has Ever Told
2. Promising To Help Just To Steal Back His Key
Spearhead From Space is Jon Pertwee's first serial as the Third Doctor, disorientated and stranded on Planet Earth. He has just undergone a forced regeneration, with Patrick Troughton's Second Doctor spinning off into oblivion at the hands of the Time Lords. His TARDIS is sent to Earth, now in full colour, though it is stripped of certain parts. The Doctor, however, is not aware of this.
Collapsing after his arrival, he is taken to a hospital. There, he is quickly located by Brigadier Lethbridge-Stewart and Dr. Liz Shaw, though of course, they don't recognise his face. Meanwhile, the Nestene Consciousness and the Autons have begun an assault, meaning that if there was ever a need for the Doctor, it was then.
The Time Lord awakens, seemingly very preoccupied with finding his shoes. He doesn't know that U.N.I.T. has nicked the TARDIS key that he stashed in them. Once he does discover this, his devious side emerges. He promises to help Shaw in fighting the alien threat, though he appears frustrated by the lack of technology available to him. He convinces her to steal back his TARDIS key, claiming that what he needs is aboard. As soon as she hands it to him, he nips inside, slams the door shut, and prepares to dematerialize.
The Time Lords removed crucial parts of the TARDIS, leaving him stranded and deeply ashamed of his actions as he steps back outside to face Shaw.