Bill Potts works in the canteen, but she’s the cleverest person in the university. So when Bill bursts into the Doctor’s life, he gives her an education only he can offer. Along with the Doctor’s friend Nardole, they face sinister emojibots who smile as they obliterate, decaying monks wielding an ominous ancient truth, and one of the Doctor’s oldest adversaries – the Mondasian Cybermen. And deep below the Doctor’s quarters, something lies locked in a vault. Something the Doctor fears, but cannot live without. These adventures will test the Doctor's resolve in terrifying new ways. But he will always fight for what’s decent and kind. Without hope. Without witness. Without reward.