Tommy is unable to recall the events of the beach-house fire for which he is under investigation for. Meanwhile on the home front, he disapproves of his daughter's rebellious behavior. Richard wants Franco to marry Natalie so he can have more freedom. Lou and his new girlfriend decide to make love in the "holiest" of places. Newlywed Garrity is uncomfortable with Maggie's collection of porn movies.
Tommy meets with Sheila in hopes of finding out what really happened on the night of the fire. Lou has his sights set on a new recruit who can really help the squad's basketball team. Teddy is released from prison. Tommy's daughter Colleen is believed to have run away from home.
Tommy confronts Colleen and her new boyfriend. Probie must make a crucial decision regarding his terminally-ill mother so he asks Tommy for advice. Natalie is upset at Franco for not considering marriage. The Chief is forced to leave the firehouse because of health issues and decides to take a desk job. Tommy resists the advances of the volunteer firefighter who previously pulled him out of a fire.
The firehouse learns of the Chief's suicide. Tommy agrees to buy things for his daughter Colleen in exchange for her keeping in contact. He and Janet decide to see a marriage counselor. Franco plans on proposing to Natalie. Garrity considers divorcing Maggie.
After the death of Chief Reilly, the crew of 62 Truck gets a new chief. Tommy suffers embarrassment during a hockey game against the NYPD. Franco works up the nerve to propose to Natalie, while Sean tries to talk Maggie out of a divorce. As Janet's depression deepens, Sheila makes a surprising proposition.
A devastating fire has a profound effect on the members of 62 Truck. Tommy wrestles with his feelings about the baby. Alicia returns with a propositions for Franco. Lou makes a tough decision about Theresa.
While Janet exacts revenge when she learns Tommy gave her baby to Sheila, thus ending all attempts to repair their relationship, Franco questions his proposal to Natalie by visiting Alcia and learning how he really feels. Tommy faces new ghosts and a bottle of vodka, dates the Chiefs daughter and realizes, at Mick's suggestion, that he needs a meeting. Mick visits Sean and reveals that Maggie is safe but needs an intervention. Mike gets a new apartment and new furniture and injured on a call.
The Gavin family stages a duo intervention after several disturbing family calls. The mysterious girl from the restaurant leaves Tommy wanting for much more. In order to get her baby back, Janet must take matters into her own hands. A depressed Mike calls Tommy in a moment of despair.
The Gavin family AA group's first meeting doesn't go exactly as planned. Tommy bribes Colleen for information on Janet. Franco learns the truth about Natalie from Richie while Lou contemplates revenge on Cousin Mike.
Tommy goes on another memorable date with Beth for the sake of the crew. Black Shawn proves himself in an unexpected arena. Franco realizes what he's really lost while Latrina shows she knows how to keep Lou happy. Dad gives Tommy some insight into his childhood.
Tommy plays hero in someone else's uniform which causes confusion in the firehouse. Colleen suffers heartbreak and takes it out on Tommy. Natalie asks Franco for a favor. A rift between Mike and Black Shawn nearly leads to blows. Tempers flare between Tommy and the Chief Feinstein after Tommy makes a move on his daughter.
The spotting of Jimmy's "ghost" is the talk of the firehouse. Colleen blames Tommy for her failed relationship, while Tommy figures out a way to fix his own. Franco and Natalie come to an understanding, while Lou, Mike and Latrina come to an understanding of their own. Tommy and his father take in a ballgame.