Infernal Affairs III is a 2003 Hong Kong crime thriller film directed by Andrew Lau and Alan Mak. It is the third installment in the Infernal Affairs film series, and is both a sequel and a semi-prequel to the original film, as it intercuts events before and after the events in the first film. Andy Lau, Tony Leung, Kelly Chen, Anthony Wong, Eric Tsang, and Chapman To reprise their roles again, joined by new cast members Leon Lai and Chen Daoming.
Infernal Affairs III uses parallel storytelling, flashing between the past and the present.
Undercover cop Chan Wing-yan seeks to uncover the link between triad boss Hon Sam and the mysterious Mainland Chinese triad boss Shen Cheng. Since Hon's ascension to the seat of triad boss was due to Ngai Wing-hau's death in Infernal Affairs II, Hon is suspicious of all his followers for fear they might usurp his position. He tests Chan's loyalty by ordering Chan to smash an ashtray on Shen's brother during a negotiation, resulting in Chan's arrest by Inspector Yeung Kam-wing. Yeung tells Chan that though Chan doesn't recognise him, Yeung recognises Chan and warns him to "be careful". After being released, Shen smashes a bottle of liquor on Chan's
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