19-year-old hooligan Tommy (Anson Boon) revels in a life of drugs, parties, and violence. Until one night, he is abducted by an unknown figure (Stephen Graham). Though he is no stranger to violence, he is horrified when he wakes to find himself chained in the basement of the isolated suburban family home of Chris (Graham), and his near-spectral wife (Andrea Riseborough). The family sets out to reform Tommy's unruly behaviour, forcing him to comply with their relentless mind games or seek escape at any cost.