For Mother's Day weekend, Big Dee Dee and Dee Dee vacation at an exclusive spa. Not to be outdone, Phyllis and Mona do the same, and end up in the room next door. The weekend quickly goes from weird to worse when Dee Dee blurts out that she wishes her mom was more like Phyllis.

Mona fears that her new man is too good to be true, so she searches for his hidden major flaw. Dee Dee accuses her of being paranoid, but soon discovers that Mona has reason to be wary, as Roland is living out of his car. Big Dee Dee considers having her breasts enlarged, but winds up receiving comfort from Phyllis as she faces a potential health crisis. A bored and desperate Dee Dee puts on a show for an apparent peeping tom in the building across the street from her apartment.

Dee Dee begins work as a sports agent, but clashes with a cocky co-worker. They are both upset when their boss forces them to work together to bring in a hot football player. Meanwhile, Adam recommends that Mona and Spencer follow his lead by signing up for an online dating service. They decide to write each other's profiles after having difficulty completing them on their own.

When Mona mistakes a dinner date with a handsome reporter as a personal affair, she unwittingly gets quoted in a music magazine saying disparaging things about one of her music label's artists that ends up getting her fired. Meanwhile, Dee Dee utilizes her law school knowledge to try to get the story retracted.

When Dee Dee becomes frustrated with Neil because he does not seem interested in getting intimate, he divulges that he is celibate. Meanwhile, Mona is under pressure at work and takes up smoking again, but she is too embarrassed to admit it and tries to hide it from her family.

After Mona complains about being bombarded with demos and Spencer's refusal to pay back his debts, Dee Dee encourages her to become more assertive and not let people take advantage of her. Mona follows her advice and re-possesses Spencer's new jacket and shoes. However, Dee Dee's words come back to haunt her when her sister refuses to listen to a demo by Dee Dee's handsome and influential new boyfriend. Meanwhile, Phyllis enjoys being pampered at an expensive shoe store after a salesgirl mistakes her for Big Dee Dee.

Mona fears a lonely Valentine's Day, but her tears may be for naught when two men from her (recent) past both ask her on dates. Also, Dee Dee is miffed that Neil would choose work over her. Meanwhile, Big Dee Dee is angry with her husband, who also chooses work over her.

After hiding the relationship for a month, Dee Dee reluctantly introduces Carter to her parents. They are surpisingly supportive. However, Big Dee Dee immediately goes to Mona and pleads with her to try to sabotage the relationship, as she and Charles believe that Carter is completely wrong for Dee Dee. Dee Dee is furious, and winds up surprised by Carter's reaction to the situation. Meanwhile, Kai provides Mona and Spencer with an assistant, who livens up the office but doesn't seem to do any actual work.

Mona decides to embrace her birthday for a change and throw a party honoring Dee Dee and her. However, the event is spoiled by Phylllis's gift to Mona: a certificate to have her eggs frozen at a fertility clinic. Meanwhile, Dee Dee receives a great job offer with a law firm, but decides to pass because her instincts tell her something else will come along. Her friendship with an NBA star soon leads to a new opportunity for a career.

After Dee Dee complains about Brett's sexist treatment of her, Charles and Spencer show up at the office to confront him. Their actions backfire, as everyone at the office begins thinking of Dee Dee as a "daddy's girl." Dee Dee, with encouragement from Mona, Phyllis and Big Dee Dee, sets out to prove herself by trying to land a successful athlete who has refused to sign with any agent.

After finding out her rival will be writing her six-month performance review for the agency, Dee Dee makes an effort to tighten up her relationship with Brett outside the office. The two have a little too much to drink one night and wake up the next morning in Dee Dee's apartment clueless as to how they got there. Mona and Spencer trick Adam into thinking he won a sweepstakes.

Kai reluctantly agrees to give a shot to Spencer's friend RJ Jackson, a talented and successful singer with a reputation for partying. Spencer has difficulty reining in RJ, and must resort to desperate measures to get a track recorded before the deadline. Meanwhile, Big Dee Dee decides to return to the stage after helping Adam prepare for an acting showcase.

Dee Dee makes a date with her favorite author after meeting him at a book signing. All appears to be going well, but Dee Dee reconsiders the relationship after learning that Carter has full custody of his two young daughters. Meanwhile, Phyllis begins snapping at everyone and seeks refuge at Mona's apartment after disagreeing with Ray's decision to take on another shift at the radio station.

After Dee Dee bests her at an online word game, Mona grows frustrated by the fact that she always loses to her sister. She becomes determined to beat her at something, and sees her opportunity when Dee Dee organizes a poker party for one of her law school professors. Their mothers decide to crash the event, where Phyllis winds up winning Big Dee Dee's wedding ring in the pot. Meanwhile, Adam tries to get access to a copy of Spencer's personal music playlist.

Mona goes against her initial instincts and decides to attend her ten-year high school reunion, where her professional accomplishments cannot protect her from the cruel comments of a pair of former cheerleaders. She perks up after a successful classmate takes an interest in her. Meanwhile, things do not go as planned for Spencer when he meets his on-line sweetheart in person; and Adam tries to get rich by stealing company supplies and selling them on the Internet.

Dee Dee has difficulty preparing her law school valedictory speech because she is uneasy about the fact that she doesn't have a post-graduation job lined up. Big Dee Dee worsens the situation when she suggests that she give up on her career and just look for a man, then tricks her into going on a blind date. Meanwhile, Mona tries desperately to prevent her mother from moving into her neighborhood.

Dee Dee and Brett run into problems with their client, a talented pitcher who won't sign his new contract because he wants to devote more time to his musical aspirations. Dee Dee asks Mona to listen to the man sing and dash his dreams of music stardom; but Delicious winds up wanting to sign him, leading to a rift between the sisters. Meanwhile, Big Dee Dee must break some bad news to Phyllis after Coco chases one of Phyllis's cats into traffic.

Dee Dee receives the opportunity to appear on a sports talk show, only to humiliate herself by falling flat on her face. Mona objects when Spencer and Adam constantly give in to Dalis's petty demands. She finally puts her foot down, with disastrous results.

Mona, a self-reliant record executive, is set to move into the penthouse apartment that her father has always promised her. But her plans of getting settled in her new apartment soon come to an end when she learns that her spoiled half sister, Dee Dee, and Dee Dee's overbearing mother also lay claim to the apartment. The sisters' relationship is further strained when Dee Dee inadvertently attracts a man whom Mona was pining for.

While Mona struggles to find work after poisoning her reputation in the record industry, the reporter whose article got her fired tries to make amends and sets up a meeting for Mona to plead her case to Big Phat Slim Jim, the artist she disparaged, in hopes of getting her old job back. Meanwhile, Mona's family and friends offer their encouragement and support in their own special ways during her difficult job search.

Mona and Dee Dee attend Neil's wedding, where their conversation with the already-nervous bride in the bathroom leads her to call off the wedding. Mona believes they should stay out of the situation to avoid causing further harm; but Dee Dee insists on taking in the devastated Neil when he shows up on her doorstep. Spencer regrets giving an overly generous tip to the stripper at Neil's bachelor party, and tries to get the woman to return it. Meanwhile, Big Dee Dee fears that she and Phyllis may actually have things in common after they run into each other at a funeral and discover that they both dated the deceased.

Mona grows very nervous about her role in selecting the Fast Track winner, especially after Kai decides to step aside and leave the decision about whom Delicious will sign to Mona. Dee Dee urges Mona to have confidence in her abilities. After a workshop, studio session and live showcase, Mona, Jimmy Jam and Terry Lewis select the winning act.

Mona tries to comfort Dee Dee after Carter appears on a talk show and says that he is seeing someone. When she later discovers that Dee Dee and Carter have secretly reunited, an angry Mona declares that she will not help Dee Dee pick up the pieces after the new ""casual"" relationship fails. Meanwhile, Spencer tries to get into photography in the hopes of getting rich; and Dee Dee and Big Dee Dee face a crisis involving their hair stylist.

Mona realizes that she needs to slow down her relationship with Chase after they start spending so much time having sex that it begins to affect her job and other aspects of her life. Dee Dee plans a "legends ball" on behalf of her mother (who is depressed because of her floundering acting career), but finds that none of the invited guests want to attend. Spencer buys a gigantic new truck that soon leaves him financially strapped because he can't afford gas.

After throwing together a baby shower for Neil and Janet, Dee Dee becomes concerned by the fact that she is the only person in attendance who is not attached. She begins to question her life and decision to pursue her career so aggressively. Meanwhile, Mona worries that her lack of maternal instinct could have a negative effect on her relationship with Chase. She tries spending time with Drew, and receives some advice from Big Dee Dee.