阿牛自小無家，所以愛偷看別人的家，因此遇上在床底生活的阿海。

阿海疼愛阿妹，由于父母很早離世，兩人被福利署人員帶走。后來阿妹被收養，五年后漸漸融入新家庭，而阿海仍然過著躲昵生活。

一天，阿海偷偷探望阿妹時，養母突然回家，情急之下阿海被推到床底，並開始阿妹的床底生活。此后兄妹變得不尋常，阿妹想為哥哥生孩子，阿牛揭穿了這個秘密、改變他們一生……

In the god-forsaken satellite city of Tuen Mun, 13-year-old Cookie suspects she's pregnant. Lately things have not been going her way. Her mother left; her father ignores her; her best friend is in reform school; and her boyfriend is off selling bootleg VCDs in bustling Mong Kok. Flanked by her ride-or-dies Banana, Sissy, and Bean-Curd, she journeys into town to find an abortionist.

This is the story of Yan, a young woman haunted by fleeting images of what she believes to be dead people. Told that it is all in her mind by her psychologist Jim, Yan still cannot find any other explanations for her visions. Soon, her suspicions are confirmed when Jim begins seeing the same things she does and the two begin to unravel a mystery that leads to a forgotten past