Northumberland 1970s. 14-year-old Sammy is deposited at an isolated children's home by his mother and her partner. That first night he is very upset, but his grief lessens as he makes friends with wise-cracking Billy and a streetwise yet sensitive girl called Ruby.

Northumberland, 12 years later. The friends are reunited and, despite the years of separation, still share a bond. Billy and Ruby are a couple, with a baby on the way - a child that Billy wants them to raise together. He also announces that he has bought a house for them all to live in.

He drives them to the derelict home of their youth. Billy's behaviour becomes increasingly violent and unpredictable. At one point he handcuffs himself, Ruby and Sammy together - when they try to leave. Billy and Ruby argue vehemently while Sammy attempts to diffuse the situation. Wandering around the house, Sammy remembers incidents from their shared history...

Bernie, the bully of the children's home, persecutes new boy Sammy, destroying his possessions and taunting him about his bedwetting. Ruby rescues Sammy and draws him into her relationship with Billy. The three become inseparable. Ruby begins a teasing flirtation with Bernie that soon gets out of control.

One day Sammy and Billy discover Ruby struggling with Bernie. In an attempt to teach Bernie a lesson, Sammy hits him with a cricket bat, but Billy takes the bat and, despite protests from Sammy and Ruby, beats Bernie to death. The three bury Billy on the beach.

The present. Ruby confides in Sammy that she is leaving Billy. Eventually the three leave the house. Billy, who has got wind of Ruby's plans, drives recklessly. He sends the car careening off the road. Billy dies in the crash. Ruby and Sammy, only slightly injured, walk away with relief.