
Half-sisters Mona and Dee Dee are virtual strangers who have grown up separately and suddenly become neighbors in the same San Francisco apartment building. Mona is a budding music executive raised by her single mother to be free-spirited and independent. By contrast, younger Dee Dee is a privileged honor-roll collegian who grew up in a two-parent home but seeks her identity out of the shadow of her overbearing mother.

Spencer comes to a realization when he pretends to be Mona's boyfriend; Dee Dee decides to break up with hers.

A surprise announcement undoes Dee Dee's world; Mona attempts to make sense of her relationship with Spencer.

Big Dee Dee and Dee Dee secretly take pregnancy tests; Mona accepts that Spencer is happy with his new girlfriend (Rowena King).

Phyllis and Big Dee Dee set their daughters up with the same aspiring politician (Anthony Montgomery).