A live-action adaption of the animated film of the same name.

One victim, found dead on a London street. Four detectives, in four different time periods, must solve the mystery to protect Britain's future.

The story kicks off on Hartcliffe council estate in Bristol during the early 1980s. It follows Steven Knight, a working-class boy who has his motorbike stolen the day he buys it. Teaming up with his scoundrel friends he desperately tries to track it down before it's gone for good.

Set on a sleeper train traveling from Glasgow to London, a government agency desperately tries to intervene in the rapidly-escalating events onboard. Can two people who’ve never met, one on the train and one not, work together to save the lives of its disparate group of passengers as the Heart of Britain service hurtles towards what might quite literally be its final destination?