1980. A rising model is found brutally murdered. Months of detective work lead nowhere. Then an unknown youth steps forward and confesses to the killing. Smallbone, the disillusioned detective, is convinced he is innocent but he has his own demons to wrestle with. Meanwhile, in a deserted house far from the city, a young autistic boy called Kit is growing up with his mother. The pair are outcasts from society, but Kit has no idea why and searches for clues to help him understand himself and his history. 2001. Now a young man, Kit comes to London desperate for a resolution in his quest for identity. And in so doing reopens the murder investigation...