Season Six opens with a terrifying vision of Tommy's afterlife. Tommy later rescues a priest from a burning church as HQ puts 62 on the chopping block because of funding. The guys formulate a plan to gain local support, but Lou's medical condition threatens their hopes for salvation. Meanwhile, Colleen's drinking has gotten out of control; Teddy and Mickey try to teach Tommy a lesson; Sheila can't handle Damian's decision; Mike and Garrity do right by a dying brother; Franco finds himself in deep with Janet; and Black Shawn moves things forward with Colleen.
A terrifying vision of the afterlife leaves Tommy shaken as he attempts to reconnect with his friends and family back on the outside. At the firehouse, the crew’s fate hangs in the balance when the department decides to cut costs.
Tommy comes to terms with his hellish nightmare and attempts to do right by those around him. But when the gang gathers at the bar post save, his plans fall by the wayside.
Tommy's first day back on the job is a busy one as the crew races from call to call. By the end of the shift, the guys are all exhausted, but it's Lou who feels it the most.
With the cookout quickly approaching, the guys hatch a plan to sneak Lou out of the hospital. Sean and Mike attempt to do good, Teddy bonds with Colleen, and Father Phil gives Tommy a piece of advice that sends him reeling.
A night of heavy drinking turns ugly when Tommy blacks out and loses control. The next day, the crew struggles to put the pieces together as they search for the whereabouts of Colleen.
Tommy loses his nerve when a young driver’s recklessness reminds him of his daughter’s new lifestyle. After a meeting fails to put Colleen on the wagon, Tommy is forced to pursue a more aggressive method to get her life back on track.
When headquarters shuts down the house, the crew formulates a makeshift response to a nearby call. A face from the past stirs Tommy and Janet’s emotions as their date begins to unravel.
Needles’ political leverage catches HQ off guard, leaving them no choice but to reopen the house. Feinberg loses control, Damian saves a helpless victim, and Tommy and Sheila find themselves in hot water.
Tommy and Sheila find themselves in hot water with Janet and Mickey and realize the truth about their own relationship. Damian attempts to leave the crew, but is seduced back by the camaraderie of the brotherhood.
Tommy and Sheila do their best to adjust to life after Damian’s accident. Sheila copes with her grief, Tommy struggles to budget his time, and the guys find themselves with a new pickup ploy.