Stana Katic, Michael Dorn Stana Katic, Michael Dorn

In the aftermath of being shot in Castle's Season 3 finale, Detective Kate Beckett (Stana Katic) will be ordered to see a psychiatrist. And he is out of this world.

Castle exclusive: Meet Castle and Beckett's new boss!

Star Trek: The Next Generation

star Michael Dorn has been tapped for the juicy recurring role, has learned exclusively. The erstwhile Lt. Commander Worf will first appear in the Season 4 premiere, and at least one other episode, according to executive producer Laurie Zaks, who says Beckett's time on the shrink's couch may also hold some key answers about the evolution of Beckett's relationship with Castle (Nathan Fillion).

"It's going to dredge up a whole bunch of stuff," Zaks says. "Her conversations will enlighten how the relationship will move forward to whatever that next level is."

The therapy sessions may also help Beckett finally get some closure with her mother's murder, the investigation of which has put Beckett into her current life-threatening predicament. "I think Beckett knows that in order to move on with her life she is going to have either let go or deal with how her mother died," Zaks says.

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