When wealthy, impulsive summer girl Margot meets hardworking and steady local girl Thea in the summer of 1967, the unlikely pair become fast friends, working alongside one another in a record store and spending every spare moment together. But after an unspeakable incident on one devastating August night, they don’t see one another for ten years…until Margot suddenly reappears in Thea’s life, begging for help and harboring more than one dangerous secret. Thea can’t bring herself to refuse her beloved friend—but she also knows she can’t fully trust her either.