Five hundred years ago, when Imperial Guard Ying Wood-Cheuk (Kevin Cheng) was under orders to eliminate vampires, he got struck by lightning and became immortal being. Since then, he has taken it upon himself to rid the world of vampires, and changed his identity every twenty years lest others discover his secret.
Fate leads Wood-Cheuk to encounter Lam Mung-Name (Kay Tse), a forensic pathologist, in Holland, and Mung-Name cannot help falling for him at first sight. In an effort to hunt down Ling Fung (Joel Chan), a vampire, Wood-Cheuk returns to Hong Kong only to find out there is a complicated connection between Mung-Nam and Ling Fung. Wood-Cheuk turns himself into a late-night restaurant owner to probe into the matter through interactions with different customers.
In the course of time, he gets to know Mung-Nam’s younger sister, Lam Mung-Yiu (Grace Chan) who bears a close resemblance to his late wife four hundred years ago, as well as Mung-Yiu’s classmates at university, Ho Yuet (Chan Ka Po) and Yau Ling-Mui (Lai Wai Ling)..