Ruthless politician Mayor Tom Kane (Kelsey Grammer) sits like a spider at the center of Chicago's web of power. But underneath it all, Kane hides a crushing secret. His trusted advisors Kitty O'Neill (Kathleen Robertson) and Ezra Stone (Martin Donovan) know better than to ask questions. Kane's wife Meredith (Connie Nielson) knows nothing. Only Emma (Hannah Ware), Kane's estranged daughter, has a chance of uncovering the truth. This is going to be the toughest term yet for the Boss.
Tom Kane cements his mayoral legacy with a lavish ceremony celebrating the groundbreaking of the new modernized O'Hare terminals. Now Kane looks to the future, setting his sights on reviving a subsidized housing project. While his political future seems bright, Kane continues to battle for control over his disease.
Kane uses personal tragedy to further his agenda, poaches his nemesis's aide, Mona, and hires ambitious newcomer Ian - but will they be enough to fill the void that Stone left behind?
Kane's increasing infatuation with his new aide Mona leads him to get swept up in her enthusiasm for a housing-redevelopment project.
Kane attempts to clean house and deep-sixes longtime political cronies, while at home, Meredith and Emma want no part of a family reunion with him.
Kane's corruption sweep threatens his political hold over the City Council. His mental symptoms begin to spiral out of control - Kane can no longer tell what is a hallucination and what is reality.
Kane's moves with the housing project escalate tensions from unrest to rioting and looting. As Chicago burns, Kane secretly seeks treatment at an alternative clinic, where his past haunts him.
Kane's alternative treatment seems to have worked and he is back in control of his city. Now he must remedy his public perception, even if it means making an old friend collateral damage.
Kane reluctantly enters an alliance with a longtime foe on City Council, but he soon realizes that more serious measures must be undertaken to stave off bankruptcy.
Chicago's bankruptcy crisis means a loss of power for Kane as emergency measures are put in place, but threats by his enemies to expose him could be of even greater concern.