Ever since UPN staked Buffy the Vampire Slayer, we've been waiting for a new Chosen One to emerge and kick some bogeyman butt. With the premiere of Darklight this Saturday (9 pm/ET on Sci Fi), our patience finally pays off: Roswell ingenue Shiri Appleby comes out swingin' as Lilith, an age-old demon reprogrammed to fight the forces of evil. Sound good? It did to Miss Appleby, too.

"When you see a strong heroine like that in a script, I think it would be silly not to jump at the opportunity [to take the part]," the 25-year-old California girl tells TV Guide Online. "I knew it would be interesting, and it was. It's very odd looking in the mirror and seeing your face covered in purple [makeup] — definitely a once-in-a-lifetime experience!"

Or maybe, just maybe, twice in a lifetime. The creature feature's ending leaves open the door to a sequel (if not a series). However, Appleby says that no one's come knocking... yet. "I haven't heard anything, but I'm sure [Darklight's writer-director] Bill [Platt]'s scheming something as we speak."

In the meantime, the in-demand actress will keep busy plugging her upcoming films. Besides Havoc, Love Surreal and When Do We Eat?, she's especially psyched about Undertow, the drama that could catapult her closer to the league of her thespian idols, Julianne Moore and Catherine Keener. "It's sort of a breakout role for me," she suggests. "The character is a homeless runaway who meets up with Jamie Bell (Billy Elliot) on the road."

No matter the boost Undertow may give her career, the leading lady will continue to reserve a place in her heart for Roswell, the cult fave that replaced Romeo and Juliet with aliens and earthlings. Despite continued interest from fans, she doubts that a movie reunion will ever come to pass.

"I was just in Paris doing press for the DVD release of Roswell, and the same question came up," she recalls. "But I've only heard about it from interviewers, not from anybody who was involved with the show.

"Still, it's a wonderful feeling to know that people [remain] so interested," she concludes. "It obviously really touched some people."