When the guys have differences that they can't seem to resolve, Holly suggests couples therapy for them. But her move backfires when it becomes apparent that she is the cause of their problems.

The gang's relationships are thrown out of whack when it is discovered that there is more to Stuart than originally thought.

Chopin, the dog that Stuart lost custody of in his divorce, stays over. Phil then accidentally switches the dog with a look-a-like, after having a one night stand with another dog owner. Holly suspects that Eden is having an affair with their married boss, Mr. Hubner (James Morrison), and is even more convinced when she discovers that Eden is pregnant.

Phil's desire to sign top mixed martial arts fighter Tommy Dunbar (Craig Gellis) as a client has the guys all attending a strip club, which lands Stuart in the hospital. Meanwhile, Eden buys Holly a new bra, which provides surprising benefits.

Holly offers to help Stuart impress his ex-wife, Lorna (Janet Varney), at a ballroom dance contest, but it turns out Holly is no help at all. Adding insult to injury, it appears that Lorna and her partner (played by Dancing with the Stars pro Maksim Chmerkovskiy) are the favorites to win the competition. Meanwhile, Phil meets his female match, Kendra (Garcelle Beauvais), who beats him at his own game.

Holly starts to hear her biological clock ticking, so the guys help in her search for a sperm donor.

Holly's continuing crush on her co-worker Paul, makes her determined to find out how he feels about her. Meanwhile, frustrated with being the only roommate who cleans the apartment, Stuart hires a maid who begins to disrupt Haskell's life.

Holly flaunts her new boyfriend, Paul, and Paul invites the roomates to a great party. But Stuart sees signs that Paul may still be too close to his ex-wife.

With her mother, Majorie (Judith Light), and sister, Jill (Amanda Detmer), in town, Holly tries to impress her "perfect" sister by creating a new identity. Meanwhile, the guys are enamored by Stuart's cooking.

A professional tennis player and ladies man (Zach Braff) is in town, but he turns out to be more of a man's man instead.

The gang crashes a party on Phil's boss's yacht; a very pregnant Eden goes into labor.