hen Tan (Aaron Kwok), a private detective in Thailand, travels to Malaysia following a series of clues found in a photo. There he searches for a man called Chai, who might help reveal the truths behind the murder of his parents 30 years ago. Chen finds Zheng (Nick Cheung), a Malaysian detective born in China. Together they meet Chai's daughter, Zi-Wei (Jiang Yi Yan) who could hold the key to cracking the case.

Overview from themoviedb.org