The ceremony for the 22nd Hong Kong Film Awards was held on 6 April 2003 in the Hong Kong Cultural Centre and hosted by Eric Tsang, John Shum, Athena Chu and Anna Yau. Twenty-seven winners in nineteen categories were unveiled. The year's biggest winner turned out to be Infernal Affairs, which won seven awards, including Best Film, Best Director, Best Screenplay, Best Actor, Best Supporting Actor, Best Film Editing and Best Original Film Song. Besides the eighteen regular awards, the 22nd Hong Kong Film Awards also presented veteran actors Cho Tat Wah and Shek Kin with the Professional Achievement Award.

Infernal Affairs is a 2002 Hong Kong action thriller film co-directed by Andrew Lau and Alan Mak. Jointly written by Mak and Felix Chong, it stars Andy Lau, Tony Leung, Anthony Wong, Eric Tsang, Sammi Cheng and Kelly Chen. The film follows an undercover Hong Kong Police Force officer who infiltrates a Triad, and another officer who is secretly a spy for the same Triad. It is the first in the Infernal Affairs series and is followed by Infernal Affairs II and Infernal Affairs III.