The episode begins with everyone at the firehouse praying for Hallie’s soul. Boden tells everyone that the detectives from CPD are at the scene, investigating it. At the precinct, Casey arrives for an update and is told by Antonio that Hallie was struck on the back of the head and killed before the fire started. Casey is too stunned for words; just then Antonio is informed on the radio that the silver car that fled the clinic right after the fire has been spotted. Cops are in pursuit of the vehicle. After a cop car blocks the car’s path, the driver and his accomplice get out and make a run for it.
The cops give chase on foot and eventually nab them. Casey arrives with the detectives at the spot where the perps are being held. They claim they are crack heads, who bought the car from someone. They allegedly have no idea about the fire at the clinic. The detectives find a hidden compartment in the car and figure out that the car was owned by someone, who used it to move large amounts of dope. At the firehouse, Peter is still mad with Dawson and is giving her the cold shoulder. While the detectives along with Boden, Casey and Severide are checking out the scene of the fire, Boden gets a call. Before leaving with Severide, Boden asks Casey to stay back with the detectives, so he can follow the investigation.
Voight isn’t apparently pleased with this, but says nothing. Boden and team arrive at the scene and are informed that a woman has fallen down an open sewage duct. Boden, Severide and the rest of the team rescue the woman after some initial struggle. The detectives have a chat with the man who runs the clinic Hallie was working at. He after some persuasion reveals that the girlfriend of Jubile Bartlett, a drug dealer, had come to the clinic with a broken jaw. The cops were informed about this, which is something Bartlett did not take too kindly. At the precinct, Casey loses his cool with Voight, after Voight tells him that he has only allowed him to be with them and follow the investigation as a courtesy.
Antonio calms him down and takes him outside. Casey feels Voight isn’t going to move a finger unless someone pays him, but Antonio assures him that he has his eye on Voight. He tells Casey to go back to the firehouse and to wait for his call. Casey reluctantly leaves. At the firehouse, Severide and Shay are drawing out legal papers, so there would be someone to take care of their baby if either or both of them died. While at it, Shay and Dawson get a call. The duo arrives at a house and is informed by the cops that a 30-year-old female has been shot in the stomach. The neighbors heard the gunshots and called the cops. The duo on checking the victim learns that she is dead. Shay sees a work ID on her neck, turns out; she used to work at the same clinic as Hallie.
The detectives arrive at the scene and while they are investigating the murder, they are informed that Jubile Bartlett has been in jail for the past 4 days on a drug charge. At the fertility clinic, before Shay goes in for the procedure, Severide rubs her belly for luck. While Dawson is setting things up at the bar along with Hermann and Otis, she gets a text from Peter. She meets him at a café. Peter breaks up with her, saying he can’t get over the anger, of her not telling him what she knew. He says he needs some time to sort things out. Dawson beaks down. Peter consoles her, saying he still loves her, but is affected by this whole thing more deeply than he had thought. The detectives get a lead on man named Calvin Jackson, a drug dealer, who might have been involved in the clinic fire.
Voight decides to deal with Jackson on his own. He meets Jackson’s uncle, who tells Voight that CJ (Calvin Jackson) used to deal with a guy working in the clinic and with the guy who runs the clinic. CJ was at the clinic making a drop, when it caught fire. He came back and told his uncle about this, who told CJ to disappear. The uncle says that CJ’s contact in the clinic is a crazy dude, who knows Voight used to give him (the uncle) and his gang protection. He therefore advises Voight against catching this guy and hands him $5000 to persuade him. From a distance, Antonio sees Voight accepting the money and walking back to his car. At the firehouse, a teary eyed Dawson tells Shay that Peter broke up with her.
Shay gives her a hug and consoles her. Casey is still trying to come to terms with Hallie’s death, when Severide knocks on his office door, with a couple of cigars in hand. While smoking a cigar, Casey pours his heart out to Severide. While they are at it, Boden tells Casey that Antonio has come to see him. Antonio wants Casey to meet the head of the clinic and lie to him that Hallie recorded on her computer all the wrongdoings at the clinic before she died. He also asks Casey to tell the head, Hallie recorded that the head is a good man, but was forced into this. Antonio feels this might prompt the head to reveal the name of his accomplice at the clinic. Antonio says he and his team will be waiting outside, just in case something goes wrong. Boden is worried because Casey is being told to wear a wire.
He feels that if the director learns Casey is wearing a wire, he might pull a gun on him. Antonio concedes, that is a valid scenario and adds that he can’t guarantee Casey’s safety a 100%. Casey says that he doesn’t care and tells Antonio that he is in. While watching Casey go into the clinic to meet the head, the detectives learn that Timothy Carroll, one of the guys working at the clinic, is a serial offender. Timothy’s prints have revealed this. Inside, while Casey is telling the receptionist that he wants to talk to the head of the clinic, gunshots are heard from inside his office. Outside, the detectives hear the gunshots and immediately rush in. Casey, who is hiding behind a desk, notices a large man leaving the clinic head’s office. He rushes to the head’s office after the shooter leaves and sees the head lying on the floor in a pool of blood.
Casey chases after the shooter, who boards a train. Casey follows him into the train and so does Antonio. Voight chases after the train in his vehicle. Eventually, Casey catches up with the man, when a station arrives. Both the men fall onto the platform, while trying to wrestle each other. Carroll, the shooter, in the end places a gun to Casey’s head and asks Antonio to back off. Voight arrives at the scene and Carroll seems relieved to see Voight. Before Carroll can say anything that would implicate Voight, he shoots Carroll in the head. In the night, Voight meets a woman in a vehicle parked in an empty lot. He gives the woman the $5000 he took from the dealer and tells her that the dealer’s name is Maurice Owens. He tells her to give him a receipt for the cash and she comments, how him pretending to be dirty is helping net bad guys.
At the opening of Molly’s, which is dedicated to Hallie, Casey arrives and is overwhelmed to see the actual Stanley Cup placed in the middle of the bar. It was brought in by a cousin of Otis’. Casey relives the moments he spent with Hallie, while the whole firehouse gang listens to him fondly. In the end, they all raise a toast to her. The episode ends at this point.