It's kind of like déjà vu. David Greenwalt will be running a show about a vampire detective who is in love with a mortal woman. Where have we heard that one before?

David Greenwalt, the co-creator of the "Buffy the Vampire Slayer" spinoff "Angel" who sang the "Cordy" theme song and is the man responsible for the series "Miracles," has been signed on as the showrunner and executive producer for the CBS series "Moonlight," according to The Hollywood Reporter. Suddenly, CBS' new drama series looks a whole lot more interesting - or confusing, to viewers.

"Moonlight" centers on a private investigator (Alex O'Loughlin), who is a vampire. He is joined by his former bride (Amber Valletta), the vampire who sired him 60 years ago, and a deceitful ally (Rade Serbedzija), who also is undead. The private dick's unlife changes dramatically when he falls for a beautiful mortal woman (a role which is yet to be recast).

Because of the recent history of cult favorite show "Angel" being unceremoniously cancelled by The WB network at the height of its popularity, many fans of the nearly legendary Joss Whedon show have had mixed reaction to the news. On the fansite Whedonesque, for example, reactions to the news have ranged from "Well thats weird," to "How freakin' awesome," to fears that viewers will be subjected to "Bizarro Angel."

Hiring the talented Greenwalt adds to the controversy
over the existence of the show. The question as to whether it should or shouldnt resemble "Angel" is likely to make for a nebulous audience. Some viewers are likely expecting it to be like "Angel," and will disappoint people when it's not. If the show does resemble "Angel" in any way - including the quality of the writing, characterizations, performances, and the constant juxtaposition of comedy over tragedy and back again - people may reject it for being a ripoff of the former show.

Either way, "Moonlight" has some pretty big fangs to fill. (Let's not even begin with the earlier vampire detective series, "Forever Knight.")

Still, the fact that Greenwalt will be running the show has made the show more interesting to previous fans of vampire detectives. Now all we need are vampire lawyers.

OK, that's been done before, too.

Maybe the sexcapades of young vampire doctors in love?

Greenwalt will serve as an executive producer of "Moonlight" along with Joel Silver ("V for Vendetta," "Veronica Mars"), writers, Ron Koslow ("Beauty and the Beast," "Birds of Prey") and Trevor Munson. Greenwalt's most recent work included the short-lived "Kidnapped," "Jake 2.0," "Eureka," and "Surface." He has also helmed the show "Miracles," and was a writer and producer for "Buffy." Greenwalt has written for "Profit," "The X-Files," and "The Wonder Years."

"Moonlight" will premiere this fall on CBS, taking up the Friday 9 p.m. time slot.