The episode begins, Severide’s at the doctors and she is running a few tests. Severide comes back home and gives Shay and Clarisse the good news that he can resume full duty very soon. At work Shay talks about Clarisse with Dawson. Dawson doesn’t seem too excited, as she isn’t a big fan of Clarisse. Shay realizes this but asks Dawson to be a bit more understanding, as Clarisse and her are a couple now. Shay says she needs Dawson’s support. Suddenly out of the blue, Dawson blurts out “I am sleeping with Mills”. She asks Shay to keep it quiet for now. Mills wants Dawson to meet his mom, but Dawson isn’t too comfortable with that, as it’s too early in the relationship. She wants Shay’s advice on the issue.
Just then they get a call. It’s a car accident and the driver has fled. The passenger, who is a woman, is trapped in the car and is bleeding from her head. The woman says her name is Ambrosia. She is barely in her senses and Shay sees needle marks on her forearm. The woman is removed from the car and rushed to the hospital. Turns out, the woman has ODed on heroin and it’s the fifth such incident “this week”. Casey’s mom Nancy is released from prison and Casey is there to welcome her. Her boyfriend Rick is also there with him. Casey takes her home. Severide on the other hand returns to work. Detective Antonio Dawson gives the whole team a brief about the victims of heroin overdose.
He mentions that, the dosage being given to the victims are particularly lethal and each case is being treated by the police as potential homicide. The team later arrives at the scene of a fire, in a bar. The team quickly jumps into action, as the fire is getting out of control. Later at the station, Tony tells Dawson that he is working the narcotics case by himself, and wants her to cover for him. He basically wants her to lie that he was with her the last night, and says he wants her to do this because he was working on this case. Dawson feels there is more to the whole thing than what Tony is letting on, but Tony refuses to tell her anything more. Eric, the guy who was brought in as a stand-in for Severide, seems to have a problem with him.
Turns out, Severide at one point was engaged to his sister Rene, but walked out on her just two days before they were to get married. Eric has apparently not forgiven Severide for this. Severide tries to make amends, but Eric is in no mood to do so. The two in fact nearly come to blows. Casey’s mother Nancy in the meantime pays Casey a visit at work. Casey seems visibly uncomfortable with her visit. She concludes Casey is embarrassed that she is there. Casey denies being embarrassed and agrees to give her a tour of the workplace. They run into Mills who welcomes her. Just then, Dawson arrives and Nancy recognizes her as she was with Casey during the hearing. Nancy comments on how Dawson and Casey would make an adorable pair.
Mills isn’t at all happy to hear this. Dawson too is put in a visibly awkward. Later, Mills asks Dawson quite frankly, if he is getting in the way of her and Casey. “Absolutely not, he is just a friend. I am only seeing you, I only want to see you” she tells him reassuringly. Mills is apparently convinced by her reassurance. Shay in the meantime suggests Severide tell Eric the truth, so he stops misunderstanding him. Severide though, doesn’t want to say anything as it’s all in the past and he doesn’t care what Eric thinks about him. Mouch tells Casey that something is bothering Cruz, but he isn’t ready to open up. Casey feels it’s something personal and they shouldn’t try to pry in it. Shay and Dawson run into another victim of heroin overdose.
The victim is a prostitute and is found barely alive on the floor of a hotel room. Shay discovers another girl in the loo and she too as it turns out has ODed. Tony later arrives at the hospital and tells Dawson there is a prostitution racket that is being run, and any girl who refuses to pay up, is handed bad heroin. Tony is trying to bring down this racket. Many of the girls are his informants and he is frustrated that they are “getting spiked left and right”. Casey finds out his mother is not seeing Rick anymore, but someone else. She isn’t very forthcoming about it, which is visibly worrying Casey. At work, Dawson admits to Casey that she is seeing someone else.
Severide and Eric get into a huge argument, in the workplace. “I moved on with my life ok. Maybe you should too” Severide tells Eric. “Tell me…how do you move on from seeing your sister’s car wrapped around a telephone pole, huh?” Eric retorts. Eric mentions how his sister went drinking after he broke up with her and ended up in a coma for 3 months. Eric also says how in those 3 months, Severide didn’t show up even once. Shay who is listening to all of this can no longer hold her silence and says “your sister hooked up with an ex-boyfriend before the wedding”. Shay elaborates that it was Rene who called off the wedding. Severide didn’t say anything at that time, as Eric and his family were already grieving.
Later, Eric admits to Severide, the part of his frustration is because of the fact that Rene doesn’t talk to her family anymore and half the time he doesn’t know where she is. Nancy is about to meet her new boyfriend for dinner. Casey isn’t at all happy about it. The two have a bit of an argument about the issue. In the end, Nancy calms him down and assures him she is only going for dinner and will be back by her curfew. Clarisse in the meantime gives birth to a boy. Shay is all excited and takes Severide to see the baby. A little later, Clarisse’s husband Daniel too arrives to see the baby. Clarisse hands the baby to his father. “I don’t know what your plans are. Of course I would love for you to be a part of our lives as much as you can” she tells him.
Daniel hands back the child to Clarisse and walks away quietly. A little later both Clarisse and Shay are handed a subpoena. Turns out, Daniel has filed a petition for the full custody of his son. Dawson arrives at the hospital to see the baby. Just as she is about to enter the hospital, she runs into Tony. Dawson asks a worried looking Tony as to what is wrong. He says the last girl who was admitted for an overdose has “bolted”. “Nobody has seen her for an hour” he says. Dawson sees that Tony is looking really hassled and tired and tells her that he needs some rest.
He pays no heed to her and says “I gotta go” and walks away. She sees him walking to his car, just then an SUV comes by, someone for inside the SUV shoots Tony and the vehicle drives away. She runs towards him in absolute panic. She sees him bleeding badly and yells out for help. The episode ends at this point.