Астыртын істер III: Қантөгіс қылықтар мен жасырын тыңшылар

Infernal Affairs III is a 2003 Hong Kong crime action film directed by Andrew Lau and Alan Mak. It is the third and final 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 received mixed to positive reviews, grossed $4.5 million and was nominated for seven Hong Kong Film Awards. There are two cuts of the film, both available on DVD: a 107 minute version which was released in Hong Kong theatres, and a 118 minute version, which is the directors' cut.

Infernal Affairs III uses parallel storytelling, flashing between the past and the present.

Undercover Hong Kong Police Force officer Chan Wing Yan seeks to uncover the link between Hong Kong Triad boss Hon Sam and the mysterious Mainland Chinese gang leader Shen Cheng. Since Hon's ascension to the seat of triad boss was due to the death of his predecessor, Ngai Wing Hau, Hon is suspicious of all his men for fear they might usurp his position. He tests Chan's loyalty by ordering him 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 does not recognise him, he recognises Chan and he warns the latter to "be careful". Chan is released after both Hon and Shen fetch him at police headquarters. Concurrently, Chan is prosecuted for violent behaviour. His superior, Superintendent Wong Chi shing, persuades the court to allow Chan to seek therapy, leading him to meet therapist Lee Sum Yee. Hon asks Chan to deliver arms to Shen, but he and other triad members do not show up. When Chan delivers the cargo, Shen's men discover that the boxes are empty and open fire on Chan; Shen and Chan shoot each other in the limbs during the crossfire. Shen finds out that Chan is an undercover cop when Yeung unexpectedly arrives on the scene. Yeung tells Chan that Shen is also an undercover cop working for the Mainland authorities. Yeung also tells Chan that he gained top honours when he was in the police academy due to Chan's "expulsion". The three shake hands, wait for the chaos to subside, then leave.

Senior Inspector Lau Kin Ming, Hon's ex spy in the Hong Kong Police Force, has been demoted to administrative duty pending an investigation into the deaths of Chan and Inspector B. He falsely claims that B shot Chan in the head while holding him hostage, and that he killed B in retaliation. After months of investigation, Lau is reinstated back to Internal Affairs, where he struggles to conceal his criminal past and protect his true identity. Lau later learns that Hon had previously planted five other spies in the police force, one of whom might be a fellow Security Division Inspector, Yeung. A battle of wits develops between Lau and Yeung, as each of them tries to discover the other's secret. Meanwhile, Lau suffers from an identity collapse as he loses track of reality, wrestling with guilt over Chan's death and grappling with his impending divorce from his wife, Mary. His psychological trauma deteriorates to the point where he begins to see himself as Chan. As "Chan", Lau makes it a personal mission to apprehend Yeung, whom he sees as his former self. After witnessing an incident where Lau suffers a hallucination, Lee conducts a hypnosis on him and finds out that he was Hon's spy. Lau realises his folly and knocks Lee unconscious before escaping. Lau steals tapes from Yeung's office safe, using spy cameras to determine the code. He thinks he hears recordings of Yeung relating information to Hon, and leads his Internal Affairs team to the Security Division to arrest Yeung just as Shen arrives. Lau plays a tape recording, which is actually a conversation between him and Hon. When Lau's second in command tries to arrest him instead, Lau panics and draws his gun, killing Yeung. He is immediately shot by Shen and attempts suicide by shooting himself in the neck. During a search of Lau's office, a tape is found in his safe and played. It is a recording of the song sung by Tsai Chin, given to him by Hon's wife.

A series of flashbacks play: immediately after Chan's death, Shen and Yeung meet. Shen suspects Lau. Yeung breaks into Lau's office to find tape recordings of his conversations with Hon, proving that Shen is right. Yeung is buried next to Chan in the police cemetery. Shen and Lee visit the graves and Shen says to Lee: "Events change men, but men do not change events. But these two men are extraordinary because they changed events." Lau ends up crippled and catatonic, lost inside his own mind, haunted by the spirit of Mary (Hon Sam's wife, whom he had a crush on in Infernal Affairs II) and locked in his own "continuous hell". His divorced wife Mary visits and tells him, "Our baby can say "papa" now." Before the picture fades into the next scene, the camera pans down onto Lau's fingers tapping out in Morse code, "H E L " (and then the start of another 'L' as the picture dims). Before the film ends, there is one final flashback to the hi fi shop scene in Infernal Affairs, where Lau is buying an audio system from Chan.

The film's score was composed by Chan Kwong wing. The theme song, Road to Inferno (自作自受; Zi Zuo Zi Shou), was composed by Andy Lau, Chan Tak kin and Wan Ho kit, lyrics provided by Andy Lau, and performed by Hacken Lee. Lau also sang an alternate version of the song.

Despite grossing higher than the second film at the Hong Kong box office with HK$30,225,661 (over HK$5 million more than Infernal Affairs II), Infernal Affairs III is less critically successful than the former. In his review of the film, Ed Gonzalez from Slant Magazine described it as a "jumpy, unnecessary sequel". He writes, "As overstuffed as the second film and as melodramatic as the first, it lacks the grace of the former and the whiz bang poetry of the first film’s better sequences. Like The Godfather III, it seemingly exists to buff its predecessors’ rough spots but only tarnishes their memories." Derek Elley from Variety noted its use of "copious flashbacks" and its rushed ending, writing that "there’s a growing sense of the writers thrashing around to provide a finale. This finally comes, though in bits and pieces, capped by an endless series of datelines (“seven months later,” etc.) that’s borderline self parody." He expressed that the film "is best experienced as a free riff on the previous two movies, not as a grand climax to the trilogy," and that the technical aspects "are at their smoothest, though far from the striking originality of the first movie." Manfred Selzer from AsianMovieWeb gave the film a rating of 7 out of 8, praising it for delivering "a big deal of thrill, tension and has a great story to hold everything together, which makes the third part, too, a movie experience," although he felt that "the finale feels a bit like a neverending epilogue, which didn't know where to find an end." Ross Chen from LoveHKFilm wrote that "Infernal Affairs III is not tightly crafted like the first film, nor meaty and dramatic like the second." Despite being surprised by its creative narrative, he found "more than a few massive plot holes which simply do not hold up on closer inspection." He also writes that the star studded cast "is one of the things that makes it enjoyable, if not too egregiously commercial."