In a South Yorkshire city, Ryan Sinclair, Yasmin Khan and Graham O'Brien are about to have their lives changed forever, as a mysterious woman, unable to remember her own name, falls from the night sky. Can they believe a word she says? And can she help solve the strange events taking place across the city?

The Doctor is a Time Lord: a 900 year old alien with 2 hearts, part of a gifted civilization who mastered time travel. The Doctor saves planets for a living—more of a hobby actually, and the Doctor's very, very good at it.