“The Veritas. The truth. Truth so true you can't live with it. Is that looking into hell... or seeing the light?” Everyone who has ever read the Veritas has been found dead. In a forbidden library at the heart of the Vatican, the pope urges the Doctor to read the ancient text - but can he handle the truth?

An “ancient” pyramid appears overnight. Every clock in the world begins counting down to the Earth's destruction. Three opposing armies lie ready to annihilate each other. An alien race stands ready to offer humanity a deal that could save them, but also enslave them. It's a terrifying race against time to save the world. Will the Doctor be forced to accept their help?