In a museum, the Doctor and Amy find a message from the Time Lord’s old friend, archaeologist River Song, and the Tardis arrives in time to catch her as the door of a spaceship, the Byzantium, blasts open, hurtling her into space.

It emerges that River was assisting in an investigation into a mysterious statue in the vault of the ship, which turns out to be one of the terrifying Weeping Angels. Once the ship crashes onto a strange planet, the race is now on to find the statue. When Amy is trapped by the Angel as she watches footage of it, she manages to escape, but begins to suffer from ill effects.

River teams up with some soldiering clerics, who, unbeknownst to the Doctor, are guarding her as she has been in prison. The group, along with Amy and the Doctor enter the Maze of the Dead to find the Angel. As the Angel begins to claim victims, the Doctor realises all the statues in the Maze are Angels and that the Angel from the Byzantium came to restore them. The only way to escape is to return to the Byzantium above them, but can the Doctor get his party there before it is too late?…

The two-parter continues next week.