Donny and Zoe are back from their escapades in 29 Locks. This time they must get out of Calais before they both end up in jail.

21 MILES revisits the much-loved protagonist of 29 LOCKS two years after his canal boat adventure as a fifteen-year-old. Older, wiser and more confident, life is going well for the former gang member who'd escaped a brutal life of criminal exploitation. But when Donny and his best friend Zoe plan a day trip to France ahead of their sixth form exams, Donny loses his passport and is arrested as an 'illegal' migrant. To survive, he must rely on the help of unaccompanied teenage refugees, living rough in the dunes east of Calais. Can Donny use his boat skills to cross the busiest shipping channel in the world and make it home?