The Doctor has always been wary of meddling with established history. But what happens when the history books lie?
With the secrets of time travel restored to him after his long exile on Earth, the Doctor has made a test flight into the past. Accompanying him are his assistant, Jo, and an old friend, scientist Liz Shaw. The travellers realise they are visiting one of the most significant times in Earth's history - and one of the most dangerous...
It is Russia, 1916, and Europe is in the grip of the Great War. With the TARDIS missing, its crew find themselves trapped in a country on the brink of revolution.
The Doctor and Liz are soon caught up in the deadly machinations of Tsar Nicholas's court, while Jo appears to fall under the sinister spell of the infamous Mad Monk, Rasputin.