Dark Blue 107 - O.I.S
The episode starts with a shoot out in a store with two cops pinned down by masked robbers. The robbers get away but they are, in truth, Carter and member's team using a ruse to get Ty, who is undercover as a beat cop, into Lt. Fry's circle.
Carter's superior is unsure why Carter is going after a cop with an exemplary record and who has been investigated several times and come up clean. Carter only offers that an informant turned up dead after telling Carter that a drug dealer called Terry Isaiah was being protected by a cop. Carter suspects Fry is that dirty cop working for Isaiah as Fry's spectacular arrest record seems to only hit Isaiah's competition.
When Ty goes home his wife of five months, Melissa, says she thinks she might be pregnant, which pleases both of them.
Later, back at the station house, Fry and Chavez visit Ty at his desk and Fry questions the report that Ty filed, liking Ty's response when he says he always puts cops first. Fry offers Ty a coveted position on his task force and tells Ty that if he sticks with him for one year then he would have his choice of jobs in the future. Chavez offers congratulations.
In the meantime, Carter realizes he is going to need help from an outside source if he wants to take down Fry. He goes to an old associate who is on the wrong side of the law but who likes the idea of taking down a decorated cop.
Ty, now no longer needing to wear a beat cop's uniform, meets Fry and the three others on his task force on a roof top that is in disputed gang territory. Fry asks him to read the graffitti left by the gangs that lists people they have killed and those on the list to go next. Ty realizes that some of the numbers correspond to the badge IDs of Fry, Noyce, Kim and Chavez. Fry tells him that the day his badge number ends up on that wall then that's the day he knows he is doing something right.
Carter realizes that one why to get Fry out into the open associating with Isaiah is to attack Isaiah's business by pretending they are new dealers in town looking to take over.
When Fry turns up unexpectedly at his home, Ty warns Melissa with a gesture that Fry is the 'target'. Fry has come to invite them both to his home for a barbecue. After Fry has left, Ty goes to Carter as he was uncomfortable with the fact that Fry had shown up at his door but Carter does not appear concerned and 'jokes' about what wine to take, saying that he doubts anything is going to happen at a barbecue.
Carter's task force--except for Ty who needs to stay unseen--and Carter's old associate with two of his henchmen, attack one of Isaiah's drug factories, steal any cash and then destroy the equipment. Back at Carter's place a man turns up and hands Carter a holdall full of drugs that is on loan for a few days only. Carter needs the drugs for the next part of the plan.
Ty and Melissa go to the barbecue and have a good time once they start to relax, with Melissa enjoying holding Chavez's 18-month-old son. Later, Fry's men are all seated together with Noyce talking about personal problems with his wife taking custody of his kid. Fry offers to hook him up with a good lawyer. Afterwards, Fry pulls Ty aside and tells him that he has been married for 17 years and that he believes that married cops are better cops because they have something to come home to.
Carter learns of a dealer called Tumi who distributes drugs on the club circuit and decide to use him to get to Isaiah. Although Tumi thinks Carter and Dean are insane for wanting to cut in on Isaiah's territory, Carter tells him that Isaiah will be running dry so if Tumi wants to keep his customers happy then he needed to deal with them. When Tumi asks how Carter knows this, Carter tells him that he and Dean were the ones who hit Isaiah's drug factory.
The next day Ty hears Fry yelling on the phone. Fry looks anxious and annoyed when he comes out of his office and tells Ty to get everyone as he had a tip about a new buyer in town. They bust in on Tumi. Fry punches him and Tumi tells them about the new supplier. Tumi insinuates that Isaiah is pulling Fry's strings and the next second Ty believes he sees Tumi reaching fro a gun. He shoots and kills Tumi but Fry pulls up a remote control. Fry 'salvages' the situation by planting Noyce's back-up piece on Tumi so it looks like a righteous kill, and then tells Ty to call it in. Back at the station Fry and the others toasts one less scumbag on earth. Ty is still shocked by what happened and after the others leave he asks Fry what Tumi meant about Fry and Isaiah. Fry tells Ty that Isaiah is just an informant who is more valuable on the streets than in prison but once that situation changes then he will take him down too. Ty is now having doubts about the job. After Fry leaves, Chavez stares at Ty pensively through the glass doors.
Carter is angry that Ty shot and killed Tumi but Ty says he had no choice and questions why they are going after Fry as he seems legit to Ty using methods no different from the ones they regularly employ. Carter insists that there is more to Fry but it is Jamie who discovers, later, that Carter and Fry have bad history when she pulls up an old news story concerning an LAPD scandal that has a photograph of the two men walking side-by-side together.
Meanwhile, Chavez approaches Ty and tells him that Fry planted the gun when he leaned over Tumi then swapped it out for the remote when he checked if the man was alive. HE says Fry used a similar method to 'trap' him into silence and warns Ty to come clean and get out while he can. Ty asks Chavez about Isaiah and Chavez seems sure that Isaiah has something on Fry on tape, and that is why he is in Isaiah's pocket. When Ty asks him why he has told him all this, Chavez says that having a child changes a man's priorities. Ty believes him. At that moment, Fry and the others walk in and Fry seems suspicious but Ty tells him they were talking about kids.
Fry shows them a photo of Dean, saying he is the new supplier and that they are going to hit him immediately, leaving Ty with no chance to warn Dean.
When Carter returns, Jamie confronts him about Fry and carter admits that they worked together on a task force years ago where they were encouraged to do questionable things. Fry was the worst of them, a thug. He was convinced Fry sold out the others so he could retain his spotless record and gain promotions while others like Carter took a fall. At that moment they are warned that Fry intends to go after Dean.
When Fry's task force arrives at Dean's place, Fry orders Ty to remain below while the others go in. Dean runs as soon as they kick down the door but shots are heard, Ty rushes in and finds Chavez dead. Fry tells him that Dean started shooting and killed Chavez. Back at the station, Fry tells all the cops about this cop killer, showing the photo of Dean and tells the men to cuff if they have to but a body bag was better.
Carter realizes that Fry is tying up loose ends as he is expecting to be promoted to Captain. Tumi knew about Fry's connection to Isaiah and Chavez was looking for a way out and might have flipped. Ty mentions that Fry took the drugs but when he checked they were never booked in.
Ty goes to see Fry in his office and tells him what Chavez had said about him, that he was a dirty cop. Ty pretends that he doesn't care, that he is with Fry on this, and Fry invites Ty to join him in his division once Fry is made captain but first they need to deal with Terry Isaiah.
They go see Isaiah but he is angry and wants Fry to find Dean and kill him. Fry appeases him by giving him the drugs he took from Dean's place, and that is when Carter and the others burst in. At first Fry is confused saying Carter was always a sneaky son of a bitch. On hearing sirens in the background, Fry cannot believe that Carter had called the cops on him and points at Dean, telling his men that he can fix this as everyone believes that Dean is a cop killer. When he realizes that his men won't back him, and have dropped their guns and knelt down with hands on their heads, Fry realizes it is all over and drops his gun.
Back at home Carter is looking at the old newspaper clipping of him and Fry when Ty knocks. Ty is there to invite him over but he knows Carter will not come. He tells Carter about Melissa believing she was pregnant for a while and he tells him that if she ever did fall pregnant hen his priorities would change and he would leave Carter's team. Carter tells him that he has to do what he needs to do, and after Ty leaves, he crumples up the newspaper clipping.