James Marsters by Albert L. Ortega/WireImage.com James Marsters by Albert L. Ortega/WireImage.com

Now this is what I call a bloody brilliant piece of casting.

James Marsters is joining Without a Trace as a character named - get this - Detective Mars. I kid you not. Marsters himself confirms it on his website.

As I revealed in this week's Ask Ausiello, Det. Mars will be brought in to investigate a human-trafficking ring. The role is recurring, but I hear there's definite series-regular potential.

Pretty fraktastic, eh?