In post-earthquake Christchurch, teenager Laura Chant (Erana James) cares for her younger brother Jacko (Benji Purchase) while their mum (Melanie Lynskey) is at work. After school one day Laura loses Jacko, only to find him playing in a pop-up shop filled with strange toys. The creepy old shop-owner, Carmody Braque (Timothy Spall) gives Jacko a stamp on his hand and sends them on their way. But Jacko suddenly begins to get sick and Laura realises there's more to Braque, and the stamp, than she had first realised. Fearing that something supernatural is at work and desperate to save her little brother, Laura seeks help from Sorensen Carlisle (Nicholas Galitzine), a prefect at her school to whom she is mysteriously drawn. Laura discovers that Sorensen is from a family of witches. Sorensen's mum (Lucy Lawless) reveals the only way Laura can save Jacko is to 'change over' to become a witch and defeat the evil ancient spirit Braque.