Teen sensation Amanda Bynes and the lovely Jennie Garth star as sisters who move in together in New York. In no time at all, 16-year-old livewire Holly manages to unravel straitlaced 28-year-old Valerie's orderly life, which includes a promising career in public relations, a handsome and free-spirited boyfriend and her own Upper West Side apartment. The minute Holly stumbles through her door, Valerie realizes that Holly tends to jump headfirst into things. But every time Valerie sets a boundary for her younger sister, Holly leaps right over it — usually breaking something in the process. Valerie's boyfriend, Jeff, watches the sisterly relationship develop with amusement and a twinge of regret at losing the privacy he and Valerie briefly enjoyed, while Holly's pal Gary loves the new arrangement due to his unrequited crush on Valerie. The one constant is the sisters' affection and concern for each other's happiness . . . and their ability to get out of every jam Holly gets them into.