Tommy considers a risky career change; Declan launches a secret corruption probe; Rose attempts to hide her deteriorating health.
Tommy struggles with the political fallout following a destructive fire; Colin's interest in Michael's girlfriend begins to affect his work; Declan uncovers a lead.
Tommy, Eileen and the family go on vacation; Declan and Cassie's marital problems are magnified; Colin and Kath have a romantic get-together.
Tommy attempts to coax some information from the investigators when the corrupt politicians become alarmed.
Declan connects Tommy to Nozzoli after learning more about his involvement in the Waterfront Project.
As Declan begins to focus his investigation on the Waterfront Project, Tommy seeks Michael's assistance.
Tommy looks set to become Speaker when Donatello's condition worsens; with the mob, the state police and the FBI after him, Michael still is obsessed with Colin, putting everyone in jeopardy.
Tommy turns to his sister for help on his re-election campaign; Tommy and Michael's estranged cousin returns to Providence.
Colin helps Michael and Eileen cope with the death of a friend; Freddie tries to avoid war with the Italians; Tommy helps the Speaker of the House.
Rose sows unrest between her sons; Freddie asks Declan to negotiate with the competition; Tommy and Dana see more of each other.
Tommy finds himself without his normal support network; Michael considers a significant lifestyle change; Freddie asks Declan to track down a business associate.
Michael and Kath prepare for an addition to the family; Tommy tries to clean up a bad neighborhood; Eileen gains perspective; Rose struggles with aging.
Tommy's political enemies try to block his re-election; Michael's day takes a disturbing turn; Colin escorts Kath to a clinic.
Tommy and Colin try to cope with Judd's decline; Declan tries to clear his conscience; Eileen volunteers to help Mary Kate.
Rose walks out on the family on Thanksgiving morning; Freddie and Marty get a holiday furlough; Colin gets an important mission from Michael.
Freddie asks Nozzoli to kill Michael; Tommy makes a bid for the Speaker's chair; Colin and Rose grow closer; Eileen puts her foot down.
Tommy Caffee's brother returns from being on the lam; Tommy's wife, Eileen, deals with her demons via drugs and alcohol.
Tommy draws closer to Judd Fitzgerald; Eileen's lover breaks things off; Michael struggles with the changes in The Hill.
Treasury agents raid Rose's house during Sunday dinner; Michael frames Moe for murder to take revenge for bad information.
Freddie and Michael clash over a softball tournament; Tommy must balance his loyalty; Rose loses her job.
A shooting involves Declan; Tommy pays back a loan; Mary Rose gets caught; Eileen's drug use intensifies and she is arrested for erratic behavior.
Michael convinces Tommy to help a local theater; Eileen confesses to Mary Kate; Rose takes a new job.
Michael and Kath go on a road trip and he realizes that he still cares for her; Eileen tries to reform; Tommy tries for a promotion.
A bus crash shocks everyone on the Hill; Eileen resolves to atone for her sins; Marty Trio finally decides to work with the police.
Tommy and Michael's father resurfaces; Pete tries to help Eileen; Rose confronts Michael about how he makes his living.
People of the Hill attend an Irish wedding; Tommy avoids a legal trap; Declan must decide where his loyalty lies.