The Doctor has been pursued through time and captured for the "crime" of time travel. Taken to New Britain in 3550, the Doctor is sentenced to trial by combat by Mar-Kom, the ruler of New Britain. The Time Lord allies himself with Theophilus Tolliver, the inventor of Earth's first time machine, to uncover the truth about Mar-Kom.
- St. Paul's Cathedral still stands in New London.
- In a rather unusual bit of intertextuality, Theophilus Tolliver is implied to be the unnamed Traveller from H.G. Wells's The Time Machine.
- The Doctor has been placed on trial before for his actions involving time travel, (TV: The War Games) as he would again in the future. (TV: The Trial of a Time Lord)