Fiona Fung - 'Goodbye Policeman' [Infernal Affairs Trilogy Sample Soundtrack] (Film that inspired 'The Departed')

Chen, a young police officer is sent into the ranks of the local Hong Kong Triad Mafia undercover. Meanwhile, aspiring young Mafioso, Lau, joins the police force. Years later, both men are still living double lives and, as the action heats up, are led to question their allegiances