Lady Cop & Papa Crook () is a 2008 Hong Kong crime film written and directed by Alan Mak and Felix Chong, and starring Sammi Cheng and Eason Chan. Chan plays the kingpin of a red diesel crime ring who is forced to team up and co-operate with a hot-tempered police officer (Cheng) when his son is kidnapped, thus beginning an unlikely alliance between fellow police officers and criminals.
The film marks Cheng's first feature-film role after a three-year absence from the Hong Kong cinema scene, her last film being the 2005 film Everlasting Regret. After filming, Lady Cop & Papa Crook's theatrical release date was delayed several times, due to the film not meeting Chinese censorship standards, which resulted in several scenes being reshot. The film later received a confirmed Hong Kong release date of 1 January 2009 in Hong Kong and Singapore.
John Fok (Eason Chan) is the kingpin of illegal red diesel in Greater China. When an oil tanker explodes accidentally, he becomes the focus of investigation by Hong Kong and Mainland Chinese police and is forced to halt his business to wait things out. While his business rivals start closing in, a member of his household is planning to betray him. On the surface, John seems totally helpless, but in reality, he has been staging a major comeback for months. Just as he is finally ready to turn his fortune around, however, his only son is kidnapped.