The Doctor and Donna travel back into ancient history, in tonight's episode of Russell T Davies's Bafta Award-winning time-travelling drama. When they arrive in 79AD, however, they discover psychic powers and beasts of stone running riot in the streets of old Pompeii. The time-travellers face their greatest challenge yet – can established history be changed, or must the Doctor let everyone die?

David Tennant plays the Doctor and Catherine Tate plays his new companion, the runaway bride Donna Noble. Peter Capaldi, Phil Davis and Tracey Childs guest star in tonight's episode.