One day, Kai-yi confesses to her boyfriend Ji-wen that she can only eat nail clippers. Convinced that there are others like her, Kai-yi asks Ji-wen to help her open a nail clipper shop for other nail clipper eaters out there. Based on a short story by director Pang Ho-cheung, Jimmy Wan and Derek Tsang's dark comedy may be part of Pang's effort to bring his brand of sly, cynical storytelling to Mainland Chinese audiences, but the story serves up a surprising twist that shows these Hong Kong filmmakers haven't lost their edge at all.