When the trail goes cold on a murder investigation of a policeman an undercover narcotics officer is lured back to the force to help solve the case.

[Oak has just caught Tellis questioning Calvess' wife]
Henry Oak: What the fuck are you doing talking to her without me being here?
Nick Tellis: I brought her husband's things over.
Henry Oak: Yeah, and you questioned her. What for? WHAT FOR?
Nick Tellis: What is this, "mother may I"? You said we were gonna do some of this on our own, right?
Henry Oak: [pointing his finger] Some of this doesn't extend to her! And don't get fucking cute with me!
Nick Tellis: Get your hand outta my face...
Henry Oak: If you need to know what she said about anything case-related, you refer to the file!
Nick Tellis: Yeah, I looked at the files, they're thin!
Henry Oak: What you don't fucking do is talk to her without notifying me in advance! That's not the way we do things!
Nick Tellis: Why's that? What's the problem with me speaking to her?
Henry Oak: Because... the problem is every fucking question you asked her she's already answered! She's been badgered and bothered by cops and cop questions for two fucking months now, and the biggest fucking problem is her husband... is fucking... dead!
Henry Oak: Come on! Say "fuck you" again!
Henry Oak: Man, this is un-fucking-believable.
Henry Oak: The only thing you need to know about me is that I'm gonna bag the motherfuckers who killed Mike.
Latroy Steeds: I wanna see my lawyer!
Henry Oak: What did you say?
Latroy Steeds: I wanna see my lawyer.
Henry Oak: There are no lawyers, dumb fuck! It's just me and you, and I am in your shit for the duration!
[last lines]
Henry Oak: [crying] Oh, my God, Mike, I'm sorry. Oh, my God, I'm sorry! I'm sorry!
Henry Oak: I remember one night. I went with the sheriffs on a warrant raid. This dipshit was selling meth out of his apartment. Just a stop-and-pop. Broke down the door, rousted the guy. I was in one of the back rooms looking for junk when I hear something. I turn around and see these... eyes staring at me from a closet. It was a little girl. A little ten year old girl. Naked. Shaking like a leaf; she was scared to death. Her stepfather was pimping her out for rent. I wrapped her in my coat, carried her out to the squad car. I went back... and I beat that motherfucker half to death.
Henry Oak: Quit fucking picking at it!
Darnell 'Big D Love' Beery: Motherfucker, you know who killed him!
Nick Tellis: I'm about to ask you about another dead junkie named Dowd, yeah I know Dowd Indo Joe and that punk you used to roll with Jay Reed, you know how I know that don't you?
Eugene 'Deacon' Sheps: How man?
Nick Tellis: Because I was and still am a cop
Eugene 'Deacon' Sheps: A cop? your trying to tell me your a fucking cop
Nick Tellis: Word
Eugene 'Deacon' Sheps: If you a cop why didn't you try to bust me back then?
Nick Tellis: Because you're way too little to bust acorn
Eugene 'Deacon' Sheps: fuck that shit, you forget something, I used to smoke blunts with you
Nick Tellis: I don't care what you think, it doesn't fucking matter in the least, what I'm about to tell you what does matter and you're going to listen like your life depended on it, a month ago an undercover officer was murdered in a pedestrian tunnel off Houston and West Grand someone beat him up and put a gun to his head a bullet through it I don't want to hear your shit about what you don't know or what you didn't do because we both know you don't got the nut sack for something that size so I'm positive you didn't kill him
[shows him a picture]
Nick Tellis: his name was Michael Calvess take a gander buddy
Eugene 'Deacon' Sheps: Hold on a minute man you mother fuckers come up in my crib, throw hot sauce in my eyes and try to blind my ass now you want my help? You crazy?
Nick Tellis: His street name is Jimmy Fredricks you know him you know him
Eugene 'Deacon' Sheps: My bad I know this mother fucker I might've let him suck my dick once or twice
[Oak throws his head into the wall]
Nick Tellis: You're going to act like a punk or you're going to get played like one, now listen very very carefully they found smack at the murder scene a mean fucking mix you took some of the exact same stuff ten months ago and nearly killed your dumb ass you don't have the chemistry or the sense God gave goats which means you didn't do the cook, now Dowd is dead so who sold to you?
Henry Oak: A little girl being brutalized... a little girl being abused has got nothing to do with the rules and regulations and everything to do with right and wrong.
[Oak speaks with a prostitute working in cold weather]
Henry Oak: Never too cold for pussy.
[discovering that a suspect's trunk is full of guns]
Henry Oak: What, are the brothers throwing a coup?
Henry Oak: You two had better get a goddamn grove going right here, 'cause you're in a life and death struggle as of right fucking now!
[after a apprehending a hoodlum with long dreads]
Nick Tellis: Now, fucking Coolio tried to blow my head off.
Nick Tellis: What if I got killed out there tonight? WHAT IF THAT WAS ME, HUH?
Henry Oak: You two had better get a goddamn groove going, 'cause you're in a life and death struggle as of right fucking now!
[Oak has a gun at a hoodlum]
Henry Oak: You asshole! I'll shoot your fuckin' head off!
[the hoodlum starts crying]
Henry Oak: Shut the fuck up!
[getting angrier]
Henry Oak: SHUT THE FUCK UP!
Henry Oak: [to Tellis] You must be out of your fucking mind! You call up my integrity? My commitment to that kid?
Henry Oak: I am so far from fucking with you.
Henry Oak: It's impossible you're this dumb.
Henry Oak: You're fucking in America, speaking English.
Octavio Ruiz: I love you, baby! Fuck!
[pause]
Octavio Ruiz: That's a good woman.