Dr Alithea Binnie (Tilda Swinton) is content with life and comes at the world with a healthy scepticism. Despite this she encounters a Djinn (Idris Elba) who offers her three wishes in exchange for his freedom.
This is a problem because she is a scholar of narrative and knows all the cautionary tales about wishes gone wrong. He pleads his case by telling her fantastical stories of his past. Eventually she is beguiled and makes a wish that surprises them both.