Walden and Bridget go head-to-head trying to take over his company, Walden Loves Bridget Inc.; Walden turns to Alan for help.
Zoey tries to convince Walden to cut his hair and shave; Alan and Lyndsey revive their relationship.
Walden tries to loosen Zooey up by sharing some of Berta's special brownies.
When a huge storm keeps Walden, Alan, Zoey and Lindsay at home on Valentine's Day, conflict brews and relationships are strained.
Jake goes to live with Judith and Herb after learning that Alan has been dating Eldridge's mom; Charlie decides to cut back on his drinking.
When Lindsey asks Alan to move in with her, Charlie will do anything to get him to agree to it.
After moving in with Lyndsey, Alan continues to have a rendezvous with Melissa at Charlie's house.
Charlie regrets allowing Alan's girlfriend to move in when the bachelor pad is suddenly overrun by women.
Alan cares for Judith's baby and her tipsy mother; Jake uses an incriminating picture to blackmail Charlie.
Alan takes a job working for Evelyn; Charlie must mend Chelsea and Jake's rocky relationship.
After they embarrass him in public, Jake refuses to stay with Charlie and Alan.
Alan suggests that Chelsea get breast-reduction surgery, and Charlie kicks him out.
Charlie and Alan go out drinking when a date is finally set for the wedding; they are horrified when they wake up to find a strange woman in their bed.
Chelsea tries to help her beautiful college roommate get over a bad breakup.
Charlie discovers he has not been satisfying Chelsea; Alan attempts to cure his thinning hair without spending much money.
Charlie discovers that Chelsea has not been completely honest about her finances.
Charlie attempts to guide Jake down the path of infidelity while his girlfriend is away for the holidays.
Jake writes love songs to woo his ex-girlfriend; Herb and Alan hide their secret friendship from Judith.
Charlie undergoes a colonoscopy to avoid a trip to see Chelsea's bigoted parents, but he finds them in his living room when he returns home.
A bar fight lands Alan in jail; Charlie worries that Chelsea is interested in the lawyer who takes Alan's case.
When Charlie's jealousy threatens his relationship with Chelsea, he turns to Alan for help in becoming a better person; will he be able to pull it off?
Charlie returns from Las Vegas with the woman he married there, who is not Chelsea; Chelsea's dad arrives in town on a visit with his boyfriend.
Jake's new friend, Eldridge, is a bad influence; Alan likes Eldrigdge's attractive mother (Courtney Thorne-Smith).
Alan tries for an intimate night at a hotel with his new girlfriend; Charlie tries his own approach to get the "girlfriend experience."
Alan and Jake head out on a road trip; Charlie is shocked to find himself haunted by the ghosts of his ex-girlfriends.
After Charlie's license is suspended, Jake becomes his driver; Alan plans to go to Chelsea's birthday party.