A late-night cleanup turns into a nightmare for Tommy when several unexpected visitors stop by the bar. Feinberg allows Damien to ride along with the crew, but may not be prepared for the consequences.

Tommy decides to make life a living hell for his wife's new boyfriend by wreaking havoc on his business and finances. Meanwhile, Chief Reilly faces possible suspension as the result of an altercation with a fellow firefighter and Lou decides to share his poetry.

Tommy copes with a tragedy. Jerry must decide what to do when his wife's condition worsens. Sean has a crisis of faith. Lou learns some shocking facts about Candy. And the crew responds to a multi-level building fire with people trapped inside.

Tommy and Janet are brought together once again by another Gavin family tragedy. Jerry ends up not showing up for work. Mike decides it is time to look for some advice about his sexuality. Meanwhile, Maggie has a surprise for Sean.

Tommy ends up promising Janet that he will help her with the baby, but neglects to tell her about his future plans with Sheila. Meanwhile, Franco decides to check up on his daughter, Keela.

Tommy comes to terms with the reality of his broken family as a result of a shocking experience with his father. When a freak accident occurs, Franco must make a life-changing decision, and Chief Reilly is forced to expose a family secret in order to save his career.

When Janet needs more money to cover house repairs, Tommy turns to Uncle Teddy and his "little" friend to help him out with extra cash. When Franco's father has a stroke, Franco finds himself trying to juggle work and raising his daughter on his own. Meanwhile, a goodwill tribute to the firefighters lost in 9/11 goes awry and the firehouse is put in jeopardy.

The hockey game rematch between the NYPD and the FDNY is right around the corner and Tommy must figure out a plan to save himself from being pummeled by the cops who have it out for him. Tommy's relationship with Sheila is discovered by the guys and they must adhere to tradition to handle it in their own way. When Tommy is visited by his demons during a fire, Franco comes to his aid... with devastating results.

Following a meeting with Janet, Tommy has yet another confrontation with Johnny; Teddy's conjugal visits with Ellie prove to be a letdown; and Franco tries to befriend his new girlfriend's mentally challenged brother. Elsewhere, Tommy keeps his vigil at Stack's bedside.

Tommy takes one step forward by convincing Janet to leave Roger but two steps backward when she stumbles onto his latest fling. The boys convince Sean to date a woman but neglect to tell him that she is actually a he. Franco discovers he can't shake his newfound fatherly instincts.

When Tommy asks for extra vacation time, Chief Reilly tips him off on how to get a free two week vacation from headquarters. While building a deck for Tommy's neighbor, Tommy takes advantage of his "free" advice which leads him to make a bold move in reconciling with Janet.

Tommy attempts to handle the insanity of his father while defending Colleen's new lifestyle to Janet. At the firehouse, Sean and Mike the Probie unknowingly launch a full blown wager among the crew.

When Tommy discovers a secret that Janet is keeping from him, he must come to terms with the possible consequences. At the firehouse, Chief Reilly preps the boys for their new female replacement. With the help of Franco and Sean, Tommy tracks down the man responsible for Billy's death.

When Tommy struggles to help Janet in a financial crunch, he must turn to his Uncle Teddy to help him out. The new female addition to the house fights to be accepted by the guys while they do everything they can to drive her nuts. Just as Mike is getting fed up from sleeping on the firehouse couch, he is offered a helping hand with a free place to stay... at a steep price.

While Tommy attempts to make reason of the chaos in his life, he continues to defy death while pulling dangerous stunts on the job. Lou admits his infidelity to his wife and receives an unexpected surprise. When tragedy strikes his family, Tommy must come to the rescue of his father.

In the opener to the second season, troubled Tommy Gavin is having a difficult time adjusting to life at his new uneventful firehouse after the volatile split with his old crew. On top of this he is still looking for his missing wife who has kidnapped his three children and he has to come to terms with the fact that his dead cousin’s wife is pregnant with his baby. His frustrations come to a head and he has a meltdown with a street vendor selling 9/11 memorabilia.

Tommy's fate in the firehouse depends on vote by the crew. Tommy reunites with his dad. Franco and Laura's relationship grows.

Tommy asks his cousin for help in understanding the bizarre visions he's been having. The crew tries to help Laura understand the essence of male comaraderie.

Tommy has a chance at finding his kids with help from his oldest daughter. Chief Jerry asks his son for help when his wife's condition worsens.

Tommy seeks the truth about Sheila while trying to get his kids back; Lou does not like the person he has saved through a bone marrow donation; Franco's addiction puts those he loves at risk; Sean's new girlfriend habitually dates firemen.

Jerry forces the crew to attend a birthday party that his son is throwing for his boyfriend. Meanwhile, Tommy makes a move on Mariel after she tells him she might not be his half sister after all. Franco asks Laura to move in with him while Sheila tries to make Tommy jealous by showing off her new girlfriend.

Tommy starts taking Janet's antidepressants. When Sean meddles in Franco and Laura's troubled relationship he makes things worse. After a gay visitor, the crew wonders about Mike's sexuality.

When Tommy, Johnny, and Mickey confront Father Murphy it results in tragedy. Sheila needs Tommy's help with a domestic issue. Jerry decides it's time to get a nurse to care for Jeanie. Lou offers to help Candy out with her situation. And Laura discovers the truth behind Franco's poetry.

Tommy's sister suddenly shows up in town when their dad is about to inherit a million dollars. Tommy and Janet decide to renew their wedding vows. Meanwhile, Mike is worried when he finds a lump.

Janet decides to meet with Tommy after not speaking with him for months since the sudden death of their son. Uncle Teddy refuses to allow anyone to help him get out prison. Tommy is shocked when he accidentally discovers just who his nephew has been sleeping with.