Infernal Affairs is a 2002 Hong Kong crime-thriller film directed by Andrew Lau and Alan Mak. It tells the story of a police officer who infiltrates a triad, and a police officer secretly working for the same gang. The Chinese title means "The Unceasing Path", a reference to Avici, the lowest level of Hell in Buddhism, where one endures suffering incessantly. The English title is a word play, combining the law enforcement term "internal affairs" – typically the division of any law enforcement agency that would be responsible for (among other things) finding a mole – with the adjective "infernal", meant in this case as a reference not to fires or infernos in general, but specifically to the inferno of Hell ("Inferno" being the Italian word for "Hell"). Thus, the English title is both a phon