The TARDIS remains in the Underground, and senses the disruption of the timeline. It takes on the form of a woman with blonde hair and sapphire eyes and calls herself Tessa. She mentions that she has been called 'sexy'. (TV: The Doctor's Wife)
The events of this story take place two weeks after The Web of Fear, featuring the Intelligence that is contemporary to that story (not to be confused with the future Intelligence which travelled back from The Name of the Doctor) and is concurrent with The Forgotten Son although in a disrupted timeline.
Reference is made to the Doctor's companions remaining in England, including Ben and Polly, and Ian and Barbara.