The Ood have given a warning to The Doctor. The Master is returning yet that is not the biggest threat. A darkness is coming which brings with it The End of Time.

With almost everyone on Earth now recast in his image, The Master controls the Earth. He's shocked however when he realises one person hasn't changed; Donna Noble. The Doctor soon understands what the pounding in the Master's head is; it's the Time Lords, who are trying to return and re-establish Gallifrey. If they succeed, it'll mean the Last Great Time War will re-start, and all the horrors which came with it. In order to stop Rasillon's mad plan, the Doctor must make a choice. Finally, the Ood's prophecy for the Doctor becomes true, and he takes the TARDIS on a trip, to see friends for one last time, before he's to regenerate.