Ying (Tony Leung), a father addicted to his daughter Ellen (Charlene Choi), helps his beloved daughter enroll in a Band 5 school due to her unsatisfying exam results. However, this makes Ellen become a bad girl and to protect her, Ying follows Ellen to anywhere she goes. Ellen is so annoyed and yells at his poor father. Ying, heart-broken, goes to a café and meets Hung (Eric Tsang), a notorious gang leader and accidentally saves his life. Being mistaken as Hung's famed but retired private bodyguard Eagle Ying, all Ying can do is to keep pretending for his daughter's sake. Ellen gets involved in a drug smuggling business and is in peril. To save his beloved daughter, Ying takes all the humiliations and Ellen, touched by his father's sacrifice, finally understands his father's love to her.