The scene opens with Julius speeding down the road having fun as he overtakes all the cars. However, it doesn't take long for him to find danger. He has a car chasing him, and it's doing everything to keep up with his pace. So Julius, worried, calls up Dan, who suggests he calls a cop. But that's what he is doing. He has nabbed so many bad guys for Dan, that it could be any of them wanting to kill him. All Dan can tell him is to make a sharp turn and get on another road. He does, but it turns out to be a dead end. The car arrives, and out steps a man in a black suit. Julius is scared and tells him he's got friends in the police, and Dan could even break a few laws to bust his ass. However, this man is Internal Affairs Assistant Chief Guthrie. He is the one that will bust Dan's butt.
Back at office, when Dan and Jack are joshing up, Hodges announces it was nice knowing him. At the table is Guthrie and two other men, waiting for Dan to show up. Dan is livid - this man has been after him for years. While Guthrie is bending over to make Dan lose his career, it is not over things he thinks. Guthrie hands him a file - an explosives smuggling case. Dan remembers what happened 11 months back. He and Julius were canvasing an explosive smuggling in progress. A few men loaded a van with illegal explosives, and they were about to start their mission. However, Dan had an idea. He pulled out his gun, and shot one bullet. The van exploded.
Guthrie is taking Dan to interrogation, when Jack tells him to say nothing. He is going to arrange for a lawyer. When Jack approaches ADA Liz, she cannot take up cases just like that. Her job is to prosecute police misconduct, not defend it. Besides, she has read the file, but never told Jack because Dan is his partner. There have to be secrets - like the fact that he is dating her. Meanwhile, Dan faces Guthrie's interrogation. At the scene were found his informer Julius, as well as his tyre marks. Dan sees no hard evidence, and besides, it wasn't his case. Guthrie reprimands him for chewing gum in the face of his senior, and orders him to spit it out. When Dan does with a glare, Guthrie puts in his pouch. There was a chewing gum found at the scene, and he will match the DNA of this one to that.
Back in prison, the explosive smugglers are released. It turns out some dirty cop was involved, and they have been proved innocent after the internal affairs people reopened the case under Habeas Corpus. The first thing the goons want to do is take out that snitch Julius. Back at the police station, when Dan hears about the news, he is yanking Guthrie by the collar. Before long, Jack stops him, and tells him they need to save Julius. He is life is definitely in danger. Meanwhile, Guthrie is giving grief to Lt Ruiz over Dan's behavior, and he needs an office space to work on the ivestigation in privacy. Surprisingly, he wants Ruiz's office - she can use the share the floor with her men. Seeing that Guthrie is calling for trouble already, she agrees amicably.
Meanwhile, Julius is not bothering to pick up Jack's call because he is busy ogling at his girl's dress while spending time at the bar. However, Jack and Dan storm into the place suspecting the convicts have already reached him. The force the girl out of the place, announce the convicts are coming after Julius, and start looking around for anything suspicious. Jack finds a duct tape on a whiskey box, and when he opens it, there is bomb hidden under one of the bottles. Outside the bar are the convicts waiting to blow it up. Jack, Dan and Julius come out running, when the place explodes. When they get back to the police station, they are laying into Guthrie, and want police protection for Julius. However, Guthrie wants Julius' testimonial against Dan - only then will he provide protection.
Jack blames Guthrie for extortion, and is about to punch him when Ruiz intervenes, and orders them to stay out of the internal affairs' investigation procedures. Then she hands them a file to investigate someone's been stealing choppers from the grocery. However, inside the file is a note - meet Ruiz in the evidence room. When they get there, she wants Guthrie out of the building as much as anyone else. And she herself can organize for Julius' protection. However, anything they do here will be confidential and off the records. Meanwhile, the convicts return to jail to inform bad news to their boss and ally. Julius isn't dead. Back at the evidence room, Samantha digs out information on the man who might have sold the bomb to the convicts.
When Dan and Jack get to the store, it turns out the owner lost his eyes in a napalm attack, and claims he only sells military collectibles. Jack calls up Julius, who is at his place, and he is not supposed to meet anybody or go out anywhere. That is what hiding means. When the detectives leave the store without a confession, the owner's 5-year-old granddaughter lets on what she heard Jack say over the phone. Meanwhile, Guthrie is trying to prove evidence forcibly. He tries making a forensic examiner say exactly what he wants to hear, but the bullet cannot be traced to Dan's gun because it is only a fragment. They cannot find the other part. Hodges calls up Guthrie saying he has evidence, and tells him to meet at the basement. However, all he has got about Dan is the practical jokes he has played on Hodges.
No, it is damage to police property and harassment of a fellow detective. However, Guthrie doesn't want him to waste his time with this kind of stuff. When Jack returns home, he finds his place is a wreck. Julius' hat is lying on the floor. He calls up Dan to report the convicts have got Julius, but he is with Dan. He took Julius out of the place knowing his needs of hanging out and being around women, after which the goons came, saw a note from Dan, and wrecked up the place. Back at the police station, Guthrie gets to the evidence room, and blames Samantha for tampering with evidence. Tugging at her ID card, he says looks like Dan is not the only one about to lose with his job.
Guthrie makes Dan and Jack give up their weapons as part of the investigations, and later interrogates Jack. He is difficult to intimidate and does not crack under pressure from Guthrie. That is when he challenges Guthrie to call his sectional lawyer - and why doesn't he call from Jack's phone, unwittingly handing it over. The wallpaper on Jack's phone is of him and ADA Liz. He soon presumes that is the reason why she wasn't giving him the warrant. When he threatens Liz about disbarring her, she has no option but to hand over the search warrant for Dan's place. By now, the convicts have realized they need to take out Dan if they want to kill Julius. And so, they position themselves at a parking lot facing Dan's trailer home. They assume the man inside to be Dan, and start taking the shots. Overlooking is Dan and Jack, who called to warn Guthrie, but the shots have started raining too soon. Guthrie is desperate for help, but Dan is being difficult.
Before long, he tells him how to save himself. As he is in the endeavor of creating a flase target, and escaping through the panel near the bed, Dan and Jack get close to the shooters from behind, and take them out - Dan with his backup gun, which he calls the Sunday gun, and Jack with a baton, which Dan calls Sunday stick. However, one of the convicts is waiting with an explosive. As he is about to throw that on Guthrie running from the scene, Dan shoots his leg and ends up having the trajectory end up under his trailer. And boom it goes into pieces. Later, Guthrie announces he is willing to give up on the investigation, because the evidence is still inconclusive. However, he will be back on his tail if he crosses the line. The episode ends.