The episode begins seven years in the future, with Commissioner Walter Clarke still having a talk with Paul, the reporter. Back in the present, while he is leaving Margot’s after spending the night with her, Walter and she have a talk about how Holbrook set him up. Walter is mad about the fact that he will be consigned to a desk, till this whole things clears up. Walter then meets his sister, who tells him that their dad had come by the diner. She says their father wants to take her out for dinner. Walter isn’t too happy to hear this and forbids her from going with him.
Agnes insists that she wants to spend some time with her father and tells Walter to think about it. At work, Don tells Walter that he (Walter) has a meeting with an IAB officer the next day, regarding the Manasian shooting. He asks Walter to sit tight till then and work on the Duraracjzyk case, a cold case that Don has been working on for years. The rest of the team is informed by the Lieutenant about a drive by shooting. Walter sadly looks on, while the other detectives proceed to the scene of the crime. The DOA is Sheila Riggings, her boyfriend Maceio, moves coke through the projects. Maceio, who was also in the car, but is unhurt, is questioned. He refuses to reveal anything. At the precinct, Walter goes through the pictures and other details of the Duraracjzyk case.
He looks at a picture of Don and Eddie, who was his partner then, standing at the scene of the crime, looking at the body. Flashback to the scene of the crime, Don and Eddie are given details of the case by a cop. Eddie apparently was Don’s mentor just like Don is now Walter’s. The duo drives away from the crime scene at 7:20 AM September 11, 2001. Back in the present, Walter meets his dad somewhere outside. His dad was moving coke in the same area, where Duraracjzyk’s body was found. He asks his father if he knows something about the murder. His dad says it doesn’t ring a bell, but will ask around. At the precinct, Walter has a talk with Don about the Duraracjzyk case.
Flashback to Don having a talk with Mrs. Duraracjzyk, when Eddie tells Don that a dealer named Eddie Roark operates from the area where Duraracjzyk’s body was found. The duo arrives at Roark’s to have a talk with him. Roark tries to escape, but is apprehended by Don, in the nick of time. At the precinct, while they are busy questioning Roark, their superior informs them that planes have been hijacked and hostage negotiators might be required. They are told to keep working the case, until further information is received on the hijacking. While they are following the lead they received about a white Buick that was seen leaving the scene of the crime, Eddie gets called to the Twin Towers. Before leaving, he asks Don to keep working the case on his own.
From afar, Don sees smoke emanating from one of the towers and looks worried. Awhile later, Don sees a plane crashing into the other tower and is mortified. He rushes to the scene. Back in the present, a visibly distraught Don recalls that Eddie lost his life during this incident. Don got back on the case two months later, but by then the Buick had disappeared and so had much of the other evidence. While Arroyo is busy handling the drive by shooting case, his wife arrives outside the precinct. She has learnt from his credit card statements that he has been booking hotel rooms and even ordering flowers and Champaign. He tries to lie his way out of it, but it doesn’t work. She is really mad and says she doesn’t want him coming back home. Don has talk with Maceio and convinces him to reveal the name of the person, who he thinks killed Sheila.
Cody Vance, the man Maceio suspects, is a known criminal. Arroyo and Deb decide to bring Vance in. Walter, who is still working on the Duraracjzyk case, comes to the conclusion that Duraracjzyk was killed because he and Roark looked similar and someone wanted to kill Roark. Don agrees with Walter, saying he too during the investigations had felt that it was a case of mistaken identity. While Walter is having a talk with Roark, he gets a call from his father. He tells Walter that he has some info, which might help him solve the case. The team learns that an eyewitness saw Vance during the drive by, but Vance has cleared out and is nowhere to be found. He has relatives in Havana and Deb suspects that’s where he must have run off.
Walter has a talk with Don in private and says that his father told him of a hitman, who used to work with dope dealers. This hitman might have killed Duraracjzyk. Don says that it makes sense and it might be worth looking into. When questioned about this issue, after initially resisting, Roark reveals that the hitman goes by the name Pablo. Roark also reveals that Pablo runs a hardware store. Don tells Roark that he will have to wear a wire and pretend that he wants to hire Pablo. Arroyo, who is desperate for a promotion, wants to horn in on this case. Walter urges Arroyo to let Don handle this case because he (Don) deserves the promotion more than anyone else, but Arroyo refuses.
Left with no other option, Walter punches Arroyo in the face, rendering him unconscious. He then drags Arroyo into a supply closet and handcuffs him to a pipe. At the hardware store, Roark enters and tells Pablo that he is interested in hiring him. Pablo takes Roark to the basement of the store, while the team listens in on their conversation via the wire. The team hears that Roark is in trouble because Pablo has realized Roark is wearing a wire. They rush to the basement and see an injured Roark, lying on the ground. He tells the team in which direction Pablo went. Over the walkie, Don tells Walter, who is outside the store, that Pablo has escaped through a tunnel under the store. He also tells Walter where the tunnel leads.
Walter immediately springs into action. Pablo resists for a bit, but is eventually handcuffed. At the precinct, Don gets Pablo to confess to all his crimes. He then gives Duraracjzyk’s wife the news that her husband’s killer has at long last been caught. The commissioner arrives and commends Don and Walter for a job well done. Don is promoted to detective second grade and Walter is told that the investigation against him would be put to sleep. While he is on his way out, Walter has a talk with the commissioner. Walter tells him that Pablo confessed to killing 12 people, out of these, for 3 murders, someone else is doing time.
All these three cases were investigated by a detective named Ryan Bell, who is now a captain. Walter feels these cases should be reopened because a mistake was made. The commissioner tells Walter that his partner has just been given a promotion and he shouldn’t do anything to soil it. Walter realizes that the commissioner is hinting that he forget about these cases. While leaving for home from work, Agnes sees her father waiting for her. He asks her to take a ride with him. She asks him if Walter knows about this. Her father lies that he does, so she agrees and sits in his car. While Margot and Walter are having dinner at a restaurant, Holbrook comes there. He points a gun at Walter, but suddenly turns around and shoots Margot instead.
Seven years in the future Walter and Paul talk about the cases that the commissioner wanted brushed under the carpet. Paul comments how investigating those cases nearly got Walter killed, while Don and Deb didn’t make it. Paul urges Walter to tell him more about those three men, who were wrongly convicted. The episode ends at this point.