Twenty Years is the tenth episode of Season 4. It aired on December 5, 2012.
As their 20th wedding anniversary approaches, Frankie begins to think that Mike may be tiring of her company and is purposely trying to avoid her. Meanwhile, Sue frantically tries to coax Axl and Brick into helping her set up an anniversary party for their parents. Unfortunately, things don't go as planned as Brick falls into a non-responsive state when Axl spoils the end of the final Planet Nowhere book.