Anthony LaPaglia has a new foe, and his name is… Steven Weber.

Sources confirm to me exclusively that the Brothers & Sisters thesp has booked a four-episode arc on Without a Trace. Little is known about his character, except that he’ll be a thorn in the side of LaPaglia’s Jack Malone.

As I previously reported, Michael Imperioli briefly flirted with the role, but the ex-Soprano ended up joining ABC’s upcoming Life on Mars instead.

Speaking of Weber, a little birdie over at Brothers & Sisters tells me that there’s a very good chance we may be seeing Sarah’s old business partner again this season. Is this a good thing? You tell me in the comments section. And while you’re at it, feel free to handicap the LaPaglia-Weber showdown on Trace. I’m going to give LaPaglia the edge, if for no other reason than he’s the star of the show.