The film centres on a new, residential, luxurious tower block built on the eve of Thatcher’s rise to power. It contains an isolated community cut off from the rest of society. A young doctor called Robert Laing (Hiddleston) enters and is seduced by the high-rise and its creator, visionary architect Anthony Royal (Irons). Laing discovers a world of complex loyalties, and strikes up a relationship with Royal’s devoted aide Charlotte (Miller).
However, there is something else happening beneath the surface. Sensing tension amongst the tenants, Laing meets Wilder, a charismatic provocateur bent on brewing trouble. Wilder reveals the hidden life of the high-rise to Laing, who is shocked at what he sees. The residents break into violent tribes, and Laing soon finds a violence emerging in himself too.