It’s Always Sunny in Philadelphia

Upon hearing that transsexual Carmen he secretly dated is finished her sex change operation and is now married to a man, Mac protests against gay marriage (even though everyone else thinks Mac is jealous that Carmen didn’t marry him.

Dennis finds that his marriage to his crush isn’t all it’s cracked up to be and decides to divorce her, while Charlie and Frank decide to split up, and Dee finds out that Bill is using her to cheat on his wife.

The Gang purchases a boat and have differing ideas of how it should be used. Dennis, Mac, and Dee want a party boat while Charlie and Frank want a shrimp boat.

Mac finally gets his big break after correctly answering a trivia question on the radio. Mac and Charlie train for Mac’s big event. Meanwhile, Frank, Dennis and Dee take their bar-banter to the Internet with their own podcast.

The gang tries to get into a fancy upper class swim club but discover that it is "at capacity" for them. Dennis and Dee try to convince Charlie and Mac that they are upper class by pretending that they got into the swim club when they really had to settle with the disgusting public pool. Meanwhile, Mac and Charlie try to fix up their old neighborhood diving pool that is now filled with trash.

Charlie and Mac try to get their mothers to live together in Mrs. Kelly’s house after Mrs. Mac burns her house down. Frank, with the help of Dennis, tries to care for Dee when she gets sick with the ulterior motive that she will care for him when he is elderly.

The gang gets a real scare after Dee reveals that she is pregnant and that one of the guys is the father. The news forces them to enlist the help of others (Frank, Artemis, and even the McPoyles) to recall their last hazy Halloween party to determine who it is.

The gang opens a time capsule and tries to make good on the past. Dee takes another shot at acting by visiting her old drama teacher and ends up teaching his misbehaved and unmotivated drama class. Mac, Dennis, and Frank try to get their old gang member Shmity back into the gang but Charlie gets jealous of Shmity trying to replace him so he becomes the janitor at the school Dee is teaching at and claims that they are best friends.

Dee continues her new job as a substitute drama teacher and exposes her students to the culture of Paddy’s with a field trip to see The Gang’s take on the Lethal Weapon series.

Keeping the basement rodent-free drives Charlie to the brink. Frank encourages The Gang to throw Charlie a surprise party. After finding themselves in a frightening situation with "bridge people" they end up throwing Frank’s plans out the window and using Charlie’s "dream book" to plan the party.

Things go awry as the gang travels to Atlantic City for a charity benefit. When the car crashes into a tree, because they were trying to avoid hitting a squirrel, Mac, Dee, and Frank have to survive in the woods while Dennis and Charlie hitch a ride to the city. When they get there they pretend to be Frank and Mac and have the night of their lives flying on a private jet and meeting Chase Utley, a baseball player for the Philadelphia Phillies that Mac had been looking forward to meeting for long time.

Dee’s blessed event is fast approaching but the father’s identity remains a mystery...to the gang, at least. Mac, Charlie, and Frank throw a party and invite all of Dee’s former flings to try and discover who is the father of Dee’s child. Dennis has to stay at the hospital and tries to help Dee through her ordeal.

Christmas has come to Paddy’s Pub. Mac and Charlie’s Christmas spirit fades after they learn the truth about their childhood Christmases. Dennis and Dee try to get back at Frank for ruining their childhood Christmases by coming up with a "Christmas Carol"-esque scheme.

In the end The Gang comes together (in a new form) to show what Christmas means to them.