Mike and Molly have to deal with several problems as they make their way to the altar.
Two days before their wedding, Mike and Molly arrange their wedding rehearsal which turns into a disaster.
Mike's dad comes to town early to attend Mike's bachelor party, which prompts Peggy to attend Molly's bachelorette event.
Molly is put in a state of shock when she can't fit in her wedding dress just three weeks before the wedding.
Molly and Mike are left without a wedding chapel when Molly's attitude doesn't sit well with the priest.
When Peggy goes out of town, she leaves Jim with Mike and Molly in an effort to have them practice what having kids will be for them.
Mike is frustrated when Molly suggests they write their own wedding vows, and Carl comes up with an interesting approach to the task.
Molly throws Mike a surprise birthday party after learning he hadn't had one since he was a child. Meanwhile, Samuel tries online dating.
When he realizes that he forgot to make dinner reservations for his Valentine's Day with Molly, Mike tries to piggyback on Carl's plans with Christina.
Joyce's decision to have dinner with an ex-boyfriend doesn't sit well with Vince.
When Victoria ends up getting arrested for various traffic violations, Molly and Joyce turn to Mike for help.
Carl is in a state of panic when Christina wants them to take their relationship to a new level.
After getting disappointing news at work, Molly goes into a bad state which threatens to ruin Christmas.
An exhausted Molly wants Mike to help her out with Thanksgiving preparations and wedding planning.
Mike keeps cheating on his diet and tries to hide it from Molly as Thanksgiving approaches.
Mike has no idea that encouraging his mother to get a job might cause drama for Molly.
Carl attempts to get a date with an attractive woman he met at the diner.
Mike is scared when Molly's boss asks him to attend a party on Halloween, the one holiday he is afraid of.
Mike finds himself caught in the middle when Molly argues with her family over Victoria's problems with men.
Mike finally decides to leave his bachelor pad behind and move in with Molly and her family, but how will he cope living with a house full of women?
Peggy gets a huge surprise while celebrating the birthday of her boyfriend Dennis.
Now that they are engaged, Molly wants Mike to commit to planning their wedding, but her idea is in the way of Mike taking a fishing trip with his friends.