Except Holmes's twin star turns. Breaking away from the wholesome image she has honed over five years as girl-next-door Joey Potter on TV's Dawson's Creek, the 24-year-old actress plays a black-sheep daughter who invites her quarrelsome family to Thanksgiving dinner in Pieces of April, a comedy that earned raves. She also portrays a nurse who tends to an ailing Robert Downey Jr.—and lip-synchs and dances in fantasy sequences—in The Singing Detective, a remake of the celebrated 1986 BBC mini-series. "Katie's being incredibly smart this early in her career," says Detective director Keith Gordon. "People will start thinking of her as that great actress rather than that beautiful young girl."
For the Toledo, Ohio, native, that means steering mostly clear of the usual trashy teen flicks in favor of critical favorites like 2000's Wonder Boys and The Gift. (Last year's thriller Abandon, in which she starred with Benjamin Bratt, tanked at the box office.) "I think you get more tired when you're not inspired," says Holmes, who spends most of the year shooting Dawson's Creek in Wilmington, N.C. It's not exactly party central, which is fine with her. "I'm usually in bed by-midnight," says Holmes, who bought a $264,000 townhouse near the beach last June and drives her unassuming Honda to the local Starbucks for grande soy sugar-free vanilla lattes. She and castmates enjoy Monday karaoke night at a local bar. "We're always singing, like, '80s cheese," says Oliver Hudson, who as Eddie Doling is her love interest this season. Her busy schedule leaves little room for downtime with the L.A.-based Klein, 23, her real-life love interest of three years. (Before that, she dated Creek costar Joshua Jackson.) "We certainly don't see each other as much as we'd like, but we try to use the time that we have to the best of our advantage," Klein told PEOPLE last year. "What can you say? We're both busy, and the name of the game is supporting each other's endeavors."
Holmes also gets plenty of support from her family: her attorney father, Martin, 58, homemaker mother Kathleen, 56, and older siblings Tamera, 35, Holly, 33, Martin Jr., 32, and Nancy, 28. Holmes and her sisters, who attended Sundance with her, "tell each other everything," says April director Peter Hedges. "They definitely keep Katie grounded." An avid actress at the all-girl Notre Dame Academy in Toledo, self-starter Holmes found an agent her senior year and won her first movie role in 1997's The Ice Storm. For her Dawson's Creek audition she set up a video camera and convinced her mom to read the part of Dawson. It worked: In 1998 she deferred acceptance at Columbia University (she says she hopes to go to college eventually) and headed to Wilmington. "If you're following your heart and doing the right things, you're going to be fine," she says of her hectic life. Her Sundance flicks are expected to hit theaters later this year—but April's turkey-cooking scenes have already come in handy. At Thanksgiving in Toledo, Holmes says, "I was like, 'Mom, I'm good, I can totally help you do it.' "
Julie Jordan in Park City and Michaele Ballard in Wilmington