Dennis and Dee's ailing grandfather Pop-Pop is wasting away in the hospital, and they have to decide whether or not to pull the plug. But things get complicated when The Gang learns of Pop-Pop's history as a Nazi, and Mac, Charlie and Frank set off in search of the old man's spoils from the war.

With the garbage men of Philadelphia on strike, Frank concocts a plan to undercut the union and get the contract to collect the city's trash.

The gang make a disturbing discovery after crashing Maureen's wedding.

Charlie and Dee become romantically involved with two members of a wealthy family, which arouses jealousy in Mac, Dennis and Frank.

The Gang gets Freudian as they step into the therapist's office to work through their mountain of issues, but when Dennis thinks he has everyone figured out, the shrink turns the tables on him and exposes the insanity in his unique brand of pop psychology.

Mac, Charlie and Dee struggle with their faith as Charlie's mom fights cancer. Meanwhile, Frank loses his memory amidst a search for buried treasure.

With Charlie under his wing, Frank cleans up so he can get his hands dirty and help out his old company with one last big merger. An unwritten rule of the bar gets the rest of the gang caught up in a case of mistaken identity.

After slipping into an unhealthy obsession with computer games, The Gang wrestles to define the difference between the real and the virtual worlds.

Every member of The Gang has something to celebrate at Guigino's, Philly's finest eatery, but when Mac and Dennis' private dinner is interrupted by an unexpected sighting of Frank and Charlie, the in-fighting begins. Dee also turns up at a table for one, and over the course of the night, the "one-ups-manship" soars to new heights.