Sam Davies

It's 2015 and the most ambitious drilling project in history has reached deeper beneath the Earth's crust than man has ever gone before, but now the ground itself is fighting back. In the latest episode of the time-travelling drama, the Doctor, Amy and Rory arrive in a tiny mining village and find themselves plunged into a battle against a deadly danger from a bygone age.

It is the most important day in the history of Earth: the dawn of a new age of harmony or the start of its final war. The Doctor must face his most difficult challenge yet. It is a battle in which he cannot take sides and a day when nobody must die...