The TARDIS lands on a space craft and the Doctor is immediately recognized as a Time Lord, much to his surprise. He agrees to help the Minyans to locate their goal, a vessel known as P7E which is now at the center of an asteroid.
Carol turns to Joe for help after a pensioner she's been visiting regularly dies and suspicions are aroused. And Gina's pregnancy approaches full term.
A famous Arctic explorer asks for help finding his fiancée, who has seemingly vanished. With only one clue to follow, Tommy and Tuppence discover mysterious happenings at a gloomy house called the Grange.