Fifteen-year-old Donald Leroy Samson is the son of an absentee St. Lucian father and a drug-addicted English mother. Growing up in dire poverty in Hackney, East London, his life is shaped by casual violence, gang initiation, drug-dealing, and knife crime. When Donny's bored, rich, white girlfriend Zoe is offered a dubious modeling audition, the couple "borrow" a barge and navigate the 29 locks on the canal system from Hertfordshire down into Kings Cross. When they start out on their journey, the future for both of them looks unpromising, like the fake audition, but as each lock is navigated and conquered, as the waters fall then rise again, their adventure takes on a new dimension. Life will never be the same again. A gritty, urban tale of redemption.