In Willesden, north-west London, Archie Jones, a hapless Englishman saved from suicide on New Year's Day 1975, and his wartime friend Samad Iqbal, a Bengali Muslim waiter, raise their families side by side. Over two decades their children, Archie's daughter Irie and Samad's twins Magid and Millat, pull away from their fathers' plans toward science, faith and rebellion.