In 1630 New England, panic and despair envelops a farmer (Ralph Ineson), his wife (Kate Dickie) and four of their children when youngest son Samuel suddenly vanishes. The family blames Thomasin (Anya Taylor-Joy), the oldest daughter who was watching the boy at the time of his disappearance. With suspicion and paranoia mounting, twin siblings Mercy (Ellie Grainger) and Jonas (Lucas Dawson) suspect Thomasin of witchcraft, testing the clan's faith, loyalty and love to one another.