07/10/2013 04:55 pm ET Updated Jul 10, 2013

'Castle': Lisa Edelstein Lands Season 6 Guest Role With Ties To Beckett


Lisa Edelstein will join "Castle" Season 6 for a guest arc, according to TVLine.

Edelstein will appear in multiple episodes as Rachel McCord, "a tough and highly-skilled Federal Investigator whose appearance plays a vital role in Beckett’s decisions about her future."

Beckett (Stana Katic) certainly needs all the help she can get, since she was poised to move to Washington, D.C., to join a special task force in the Season 5 finale ... right up until Castle (Nathan Fillion) proposed to her in the episode's final moments.

Fans were thrilled at the prospect of a married Kate and Rick for "Castle" Season 6, but Fillion recently admitted that he doesn't know whether Beckett will even accept the proposal.

"We did not shoot the answer," the actor told TVLine. “We did that last day of shooting on a Thursday. Friday, I came in and did some looping … and then left town immediately [to] work in Canada ... I’ve not had one email, not one discussion, not a phone call about where things are going, what’s going to happen ... So I can’t even spoil anything by accident!”

Regardless, co-star Tamala Jones, who plays medical examiner Lanie Parish, is certain that viewers won't be disappointed by Season 6.

"I know the sixth season is going to be better than any season we've ever done. I can feel it from the cast, from the writers, from everybody," she said, according to OTRC. "Everybody is just so excited. I mean, we kind of felt like we would have another season but, we never take anything for granted down on 'Castle.'"

"Castle" will return to ABC in the fall.

Castle Season 5