In the Blood is a 1988 Hong Kong action film directed by Corey Yuen and starring Andy Lau and Bill Tung.

Plot

Criminal Investigation Department (CID) inspector Wah and his father, Commissioner Louis are outstanding police officers who share a close relationship. On the other hand, father and son beat cops, Uncle Maand Dan always bicker, and end up pulling their pistol at each other while giving a parking ticket. Wah and Louis attempt to mediate Dan and Ma and convinces Dan to apologize to his father, but Ma berates him, much to Louis' annoyance. Dan gets promoted to the CID and gains confidence after successfully catching a thief. Dan later participates in his first drug raid operation in a pier, where Wah manages to arrest a number of criminals but the mastermind, Fei-ying, escapes as Dan was busy gambling with some colleagues and inadvertently kicks his superintendent "Potato Knives" into the water and is put on penalty. Ma blames himself for his son's failure, but Wah convinces him that Dan just needs an opportunity to prove himself. However, Dan foils another drug bust at a bowling alley when he interrupts Wah, who was fighting Fei-ying, allowing the latter to flee again, but manage to arrest Fei-ying's girlfriend, Sze. Dan bails Sze out after finding out she is the daughter of Ma's old friend, Auntie King, but Sze runs away after being harassed by patrons at her mother's bar. Sze later questions Fei-ying whether he is a drug trafficker, which he denies.