Stana Katic, Victor Webster and Nathan Fillion Stana Katic, Victor Webster and Nathan Fillion

Castle's not going to like this one bit. On October 11th's Castle episode, he gets quite the surprise when Beckett's secret beau, Josh Davidson (Victor Webster), pops into the precinct. 

"He's this big, mysterious, hunky guy who rides a motorcycle," says Webster. "But then you'll find out he's a cardiac surgeon as well — blue collar and white collar mixed into one!"

Just how far will the smooth operator work his way into Beckett's heart? "Producers tell me they plan on having me come in and out over the next nine weeks, but they're not telling me a lot more than that," reveals the actor, who has already bonded with stars Nathan Fillion and Stana Katic over their shared heritage. "I was born in Calgary, Stana's from Ontario, and Nathan's from Edmonton, so we all have that Canadian thing going on."

But it's the bond between Castle and Beckett that Webster knows is sacred to fans. "At the end of the day, this show's about the sparks that fly between them, so maybe with the introduction of my character, they'll find out they really can't be without each other." That's no mystery.

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