Jack, a grieving man in his thirties who recently lost his wife, turns to a mysterious drug called The Return Solution, which promises to reconnect users with what once made them happy. Desperate to see her again, he takes it and is briefly reunited with her through vivid visions. But after misreading the instructions and ingesting it incorrectly, the experience turns into a physical nightmare as his body begins violently rejecting everything he eats as if it were never consumed.