On the shoreline of Lancashire's Lune Estuary, an old tramp is befriended by a young lad who volunteers with the St John's Ambulance.
Facing his parent's impending divorce and emotional upheaval, a young boy runs away and joins a gang of London street urchins who live by their wits, begging, and thievery.
Tom Foreman kills a policeman after stealing jewellery worth a fortune. He is caught and incarcerated. Prison psychiatrist Ollie Milton and Tom's wife, Val, enlist the help of ex-con "Cat" Devlin in their plot to locate the hidden jewels.