Crab Chan (Andy Lau) and Sam Law (Alan Tam) are a pair of renowned professional gamblers who are best friends. One day, a tycoon named Lung (Charles Heung) summons the two of them to his casino in Lake Tahoe to crack a scam led by a pair of Japanese gamblers, Kung (Hagiwara Kenzo) and his son Taro (Lung Fong). There, Crab and Sam also meet Koyan Tong (Idy Chan), a rich heiress from Hong Kong who is on vacation in the United States.