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.

When Dee Dee befriends Spencer, Mona becomes concerned that her sister is stealing her best friend. Meanwhile, Mona leads Dee Dee and Spencer into believing she is still dating Brian the exterminator even though he hasn't call her after their very hot date.

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.