Tommy Gavin is grappling with the death of his father as the season opens, along with the new man in Janet's life (guest star Michael J. Fox). The crew devises a business plan to open a bar, which turns into a lucrative venture, but also a temptation to Tommy, who continues to struggle with sobriety. Sean faces a health issue with no easy solution, while Needles struggles to garner respect and maintain control of the firehouse. Meanwhile, Sheila attempts to purge herself of Tommy and allows Damian to pursue a future as a firefighter. Conspiracy theories about 9/11 ruffle more than a few feathers, brought on by the arrival of an intriguing foreigner. Under the shadow of a haunting past, the crew continues to look to the future and realize that salvation often lies where you least expect it.