LOS ANGELES — Alicia Silverstone leaned out of the upstairs window of her two-story house in a woodsy section of the Hollywood Hills. Toothpaste spilling from her mouth, she shouted cheerfully, “Be down soon. I’m brushing my teeth!”

Judging from the dorm-room-during-finals state of her bedroom — unmade bed, clothes strewn everywhere — her busy schedule demands she be in multitasking mode. She had recently returned from Montreal, where she had shot a horror film directed by the Austrian team of Veronika Franz and Severin Fiala (“Goodnight Mommy”), and this May morning she was collecting belongings from the floor that she wanted to bring to the Pacific Palisades-based set of “Judy Small,” a low-budget comedy. “Script,” she said aloud. “Wallet. Shoes.”

“When I’m in a rush,” she added, “I pack crazy.”

The array of rumpled blouses and hastily discarded jackets is a far cry from the computerized closet Ms. Silverstone is indelibly associated with, the one that was color-coded, organized by season and programmed to mix and match outfits. Yet such is the enduring power of her performance as Cher Horowitz in the 1995 coming-of-age teenage comedy, “Clueless.” Made for a modest $12 million, the film grossed more than $56 million domestically (nearly $120 million when adjusted for inflation), and generated a wave of teenage girl copycat movies and predictions of superstar status for Ms. Silverstone. What followed instead was an entertainment industry chain reaction: some big paydays, a few box office failures and a “who-does-she-think-she-is?” backlash. And even though Ms. Silverstone has spent the last two decades maintaining a steady, low-wattage career filled with roles in small films, television and theater, she is still one of those actors who make people wonder if she’s even acting anymore.