It's 1953: eight-year-old Jono's parents abruptly leave show business and move home to the heart of industrial South Wales. Born in a provincial theatre, show business is all Jono knows, but his life is about to change forever. After a life on the road, he finds unusual solace amongst the characters of Cwm Teg, most significantly in the home of the exotic Peg and her boys, Pip and Frankie. Over a summer of adventure, discovery, coming of age and sexual awakening, Jono learns that family isn't always what you'd expect. And as his friendship with Peg's boys turns into an unshakeable bond, Jono realises that his whole life will be affected by them and the pull of the valleys.