The surprise return of Dennis and Dee’s estranged father causes Dennis to accidentally run over Charlie. With his legs now broken, Charlie must use a wheelchair. He soon realizes that being crippled isn’t so bad and takes advantage of the situation. Once Mac, Dennis, and Dee see the benefits, they all pretend to be handicapped as well.

The gang learns that they are about to lose their bar because their new Israeli neighbor purchased the land that Paddy’s sits on and is forcing them to evacuate. To stop this from happening, they must resort to a series of extreme methods in order to keep their bar.

Dennis and Dee are fed up with their father taking over the bar and leave the business to go and pursue their dream careers. In order to buy more time, they decide to go on welfare but accidentally become crack addicts in the process. Meanwhile, Mac and Charlie try to fill the void that Dennis and Dee left. They take advantage of the work-for-welfare program so that they won’t have to pay their new employees.

In order to get out of doing the grunt work at the bar, Dennis devises a plan to blackmail Charlie. However, when Mac reveals that Dennis’ mom tried to have sex with him, Charlie sees this as a way to get back at Dennis. Dee then gets involved when she goes to Charlie requesting her old job back. And so begins an elaborate series of backstabbing and double-crossing, with Charlie as the mastermind behind it all.

After getting ditched in an alley with a mugger, Dee begins taking boxing lessons with Frank to learn self-defense. Tired of getting pushed around at the gym, she turns to steroids for help. Mac and Dennis insist that learning fighting techniques is useless in the real world. Once they see how much money can be made in an underground fighting match, they sign Charlie up as a fighter and train him to withstand constant beatings.

The gang must perform community service for blowing up a building. Mac, Dennis, and Dee get stuck coaching two kids’ basketball teams, which Frank sees as a gambling opportunity. In addition to interstate sanitation, Charlie must attend Alcoholics Anonymous. It is there that he runs into the coffee shop waitress, and she decides to be his sponsora "a decision she’ll soon regret.

The gang finds a water stain on the wall that resembles the Virgin Mary and use it as a way to bring in more money to the bar. It also brings in an old high school classmate of theirs who is now a priest. Frank wants him to bless the stain, so they send Dee to seduce him. Mac, however, wants nothing to do with any of this, until he realizes he can change people’s lives by blessing them.

The gang decides to have Dennis run for office with the intention of dropping out and collecting the bribe money. Mac manages to solicit a bribe, but this gets him in trouble when Dennis decides he doesn’t want to withdraw from the race. Frank, angry that Charlie took over as campaign manager, joins forces with Dee to try and take down Dennis.

After a debate about constitutional rights and whether smoking should be banned in the bar, Mac, Dennis, and Frank lift all rules to uphold the American principle of freedom. This turns the bar into a place where anything goes. Charlie and Dee, disagreeing with this decision, leave and get involved with anti-smoking demonstrations.

Dee is contacted by a man claiming to be her biological father, so she and Dennis confront their parents about it. Barbara admits to having an affair and reveals that Frank isn’t their real father. While Dennis and Dee spend time with their new dad, Mac and Charlie wish they had a father figure of their own, so they visit Mac’s father in jail with the intention of bonding with him.