In the third season debut, a disgruntled Tommy mulls a risky career change, and orders Declan to launch a secret corruption probe; Rose attempts to hide her deteriorating health at her birthday party.

Tommy strong-arms the mayor for his support of a development deal, but hits a roadblock due to Michael's business dealings; Rose investigates her mysterious ailment; Eileen is passed over for promotion due to her pregnancy.

A fire kills several Latino squatters and a firefighter, leaving Tommy struggling with the political fallout; Colin's torch for Michael's girlfriend Kath begins to affect his work; Declan uncovers a lead and brings in another investigator.

The Labor Day holiday weekend finds Michael increasingly paranoid and edgy; Tommy proposes a radical lifestyle change to Eileen; Declan and Cassie's getaway highlights the growing problems in their rocky marriage.

Tommy tries to charm Declan into sharing information about his corruption probe; Rose learns the truth about her health; tension builds between Michael and Colin as they help Freddie plan a heist.

Eileen worries that her family will never leave The Hill when Speaker Donatello draws Tommy back in to help pass the budget; Declan tries to link Tommy with Nozzoli; Rose's attachment to Colin fuels Michael's anger and paranoia.

Kath and Colin worry about what Michael might be capable of if he becomes too suspicious of their relationship; Eileen goes stir crazy when her pregnancy confines her to bed; Tommy asks for Michael's help with the Waterfront investigation.

Tommy becomes heir apparent for Speaker when Donatello's condition worsens; Freddie maneuvers to get on Tommy's good side. With the mob, the state police, and feds after him, Michael's obsession with Colin puts everyone in jeopardy.