Cheung Sheung and Tze Ngor (both played by Cora Miu) are twin sisters. Tze Ngor is a lunatic and stays in a mental hospital. But out of a madcap incident, Cheung Sheung is "cheated" into the hospital, exchanging identity with her insane sister. The mad house is lived by all kinds of weirdos. The "game" is that Cheung Sheung will stay in the hospital only for a while. But strangely enough, she gradually becomes more and more ease with the way of life in the hospital until one day, she's forgotten what life is like outside, including her fiancé. (Eric Tsang). Meanwhile, Tze Ngor is out looking for her ex-husband Ma Sai Mei (James Wong) who heartlessly deserted her. She meets the postman (Meng Hoi) who has a secret infatuation with Cheung Sheung. She also makes an acquaintance with millionaire Tong (Sunman Sze Tsang). The three of them develop the most harmonious friendship ever. It's a happy ending for both sisters, each has found her own way of life... (Joy Sales)