1967: The Revolution has just started. All you need is love — but the ability to bend space and time helps. An entity called the Revolution Man is writing his graffiti across the surface of the Earth, using a drug called Om-Tsor.

Trouble is, none of this was supposed to happen. The Doctor knows that the Revolution Man isn't for real, that he's part of the problem, not part of the solution. But how is he going to convince the flower children? How is he going to convince Sam? And he doesn't dare tell Fitz...

1968: The Chinese People's Army want to defeat the capitalists. Om-Tsor is the most powerful means available, and the source is on their doorstep. If half of India is immolated — well you can't make an omelette without breaking eggs...

1969: The Revolution Man has decided. Mankind is evil, not good. The only way forward is to destroy all of it. The Doctor and Sam struggle to find him but time is running out...