For Patricia and Valarie Lockwood, it was to be an evening like any other. However, their plans are disrupted by the arrival of a mysterious stranger. A man who brings tragedy in his wake.
For Valarie's first trip through time and space, the TARDIS takes them to Venice, during Carnivale. Unfortunately, not everyone is there to enjoy the party. Captain Tomasi has a murder to commit, and he needs Valarie's help to do it.
Valarie/The Doctor is dying. Only the Doctor/Valarie can save Valarie/the Doctor, but for her/him to survive, the Doctor/Valarie will have to die in her/his place. For the Doctor/Valarie, this is journey's end.