Aboard the most beautiful train in history, speeding among the stars of the future, a legend is stalking the passengers. Once you see the Mummy, you have 66 seconds to live. Clara sees The Doctor at his deadliest and most ruthless - and finally she realises she's made the right decision. Because this is their last adventure: it's time to say goodbye to the Time Lord.

Separated from The Doctor, Clara discovers a new menace from another dimension. But how do you hide when even the walls are no protection.

In a Viking village, a girl named Ashildr is about to make a desperate mistake. The Mire are the deadliest mercenaries in the galaxy, famed for showing no mercy and Ashildr has just declared war on them. The Doctor and Clara have 12 hours to turn a peaceful village into strong fighters, ready for the deadly Mire.

“Space - the final frontier. Final because it wants to kill us.” Trapped on a space station with no oxygen, the Doctor, Bill and Nardole are horrified to discover the automated spacesuits keeping them alive are also trying to kill them!