When Mike gets sick for Thanksgiving, Molly is secretly thrilled because she won't have to cook... until Vince invites his brother, Frankie (guest star JON POLITO), to town for a homemade Thanksgiving meal.
Mike begins transforming the basement into a living area for he and Molly to live in, but the construction work is more than he - or his eyebrows - can handle! Meanwhile, Carl invites Samuel to move in with him.
Mike and Molly encourage Harry to take Victoria on a date for Valentine's Day, and everyone is shocked when she accepts. Meanwhile, Carl convinces Samuel that they will be able to meet women at the laundromat during the holiday.
Even though Mike's birthday wish is to have his wife and mother get along, Molly and Peggy can't seem to play nice as they try to plan his birthday party together. Meanwhile, Carl and Samuel compete for the same woman.
After learning that Joyce gave up her artistic talents when she became a mother, Molly decides that she and Mike need to pursue new hobbies before becoming parents. Consequently, Molly encourages Mike to take up roller-skating with her!
Mike goes on a junk food binge to cope with missing Molly, while she's out of twon for a teacher's conference. Meanwhile, Carl contemplates leaving Chicago after learning heartbreaking news from James (guest star LAMONICA GARRETT).
Molly is so focused on directing a school recital that she doesn't realize a fellow teacher is hitting on her. Meanwhile, Vince convinces Mike to join him in an unusual money-making scheme. TIM CONWAY and JIM BEAVER guest star.
In the third season finale, Mike and Carl get stuck working at the Renaissance Faire after their boss, Captain Murphy, gets dumped by Mike's mother. Later, as a tornado descends on Chicago, Mike and Molly each confess important news to each other.