Teenage David Witton lives in foster care following his father's departure from home when he was small and his mother's breakdown, and attends a rowdy remedial class. He is happiest communing with nature, nude swimming, and birdwatching with his only friend, fellow loner Fred. Though he impresses his teacher with his knowledge of nature, a school trip to a nature reserve ends in disaster when David has to kill an injured deer. Following the death of his precocious foster sister and the burning down of Fred's hut by a mob who learn that he is an ex-paedophile, David sets free his abusive foster father's captive birds and sets off in search of his real father.

David lives off the land, adopting an injured fox as a pet and sleeping in a shed. He meets Miles, the withdrawn, mute son of unhappily married Tom and Martha, and encourages Miles to speak. A grateful Martha goes to bed with David but they're discovered by Tom. David moves on, having met Jenny, a librarian part of a protest group against Blexco, the factory where Martha works and who gives him an address to help find his father.

David re encounters Jenny, now a fervent member of a protest camp occupying woods to prevent them being cleared to accommodate an airport runway. He asks her to accompany him on his search but she's determined to stay and fight. Initially uninvolved - and bonding with Ted, the under-sheriff trying to clear the camp peacefully, through a love of fishing - David is caught up in a brawl with invading security guards and, after realising Ted lied to him about the eviction date, joins the protesters in an underground tunnel.

Using the address given him by Jenny, David travels south and gets work as an apple picker. He meets Esther, a woman with whom his father Steve once lived and her daughter and, through them, locates Steve, who is now a wealthy but terminally ill recluse. Initially cool towards David, who confronts him about abandoning his family, Steve lets him stay but his time is coming to an end. David returns to the North, where Jenny is comatose in hospital - however, she seems responsive to his voice and touch.