James Marsters will trade in his supernatural garb for a role as a down-to-earth cop on "Without a Trace" this season.

The former "Buffy the Vampire Slayer" and "Angel" star has taken a recurring part on the CBS drama, Marsters says on his web site. As described there, the role sounds like it could have the potential for a multi-episode arc.

He'll play a detective who comes into contact with the FBI's missing-persons team in New York while investigating a human-trafficking ring. After initial contact with Vivian (Marianne Jean-Baptiste), he will become part of task force dealing with human trafficking.

Marsters, of course, is best known as vampire Spike on "Buffy" and "Angel." His credits also include a stint at Prof. Milton Fine/Brainiac on "Smallville," the USA Network movie "Cool Money" and guest spots on "Northern Exposure" and TNT's "Saving Grace." He'll next be seen in the feature film "P.S., I Love You," which is due for release in September.

"Without a Trace" begins its sixth season on CBS Thursday, Sept. 27.