With Sarah Michelle Gellar preparing to dust her last blood-suckers on Buffy the Vampire Slayer, and Eliza Dushku committed to the Fox pilot Heroine, who ever will protect viewers from things that go bump in the night? Our chosen one is Alyson Hannigan, aka the wickedly funny witch Willow. And series creator Joss Whedon just might agree with us, too. "The concept sounds cool," he admits to TV Guide Online.

However, that's not the reason that Whedon is crossing over the powerful wiccan from UPN's Buffy to its sister show on Wednesday's Angel (airing at 9 pm/ET on the WB). "There's nothing to suggest [a Willow spinoff in this episode]," he insists. "It just made narrative sense. We've been dealing with [the do-gooder vamp's evil alter ego] Angelus, and Willow was instrumental in getting his soul back [the last go-round], so we thought it would be interesting to speak of that history a little bit."

What's more, the boss hoped that Buffy's quirky confidante would lighten up the Angel gang during this, their darkest hour. "Alyson is a fun person to bring into the fray, because she has such a completely different energy than the Angel cast," he explains. "She's very Sunnydale — very sunshiny and goofy and childlike, even though she's matured a great deal. And Angel is so turgid and soapy, it's fun to have somebody come in and give her perspective on things.

"Besides," he adds with a laugh, "she's [Angel regular] Alexis [Denisof]'s sweetheart."

Actually, Whedon is kind of stuck on the redhead himself. If nothing else, he continues to be bowled over by her ability to make work seem like play. "Aly was being a sweetie [guest-starring when she did], because she was doing American Pie 3 and Buffy at the same time. She was working every day, including weekends, doing three different things, and she came through like a trouper."