Castle

Castle's Stana Katic likens the romantic tension between her character, Kate Beckett, and Castle (Nathan Fillion) to a dance. And in Monday's episode (10/9c, ABC) Beckett's going to switch dancing partners.

Will Castle's explosive cliff-hanger create sparks for Castle and Beckett?

When Beckett's team catches the case of a murdered thief, they look to robbery division Detective Tom Demming (Battlestar Galactica's Michael Trucco) for help with the case. And he steals Beckett's heart.

"It's really wonderful to have the opportunity to show a more sensual, romantic side to Beckett," Katic tells TVGuide.com. "I think it's great having someone like Tom Demming who is genuinely interested in Kate and is formidable enough to become a bit of a competitor for Castle."

However, Katic says Castle's response is more than petty jealousy. "It forces Castle to have some introspection as to why he hasn't approached her yet in that way and what's going on with his relationships and past romantic experiences," Katic says. "He's had a number of girls swing in and swing out. So, this is an opportunity for us as an audience to delve deeper into something he may not realize he's missing."

Check out photos of the Castle cast

So, is Beckett just trying to make Castle jealous? "I don't think she's manipulative like that," Katic says. "She has a tremendous amount of integrity and if she likes someone, she likes them. She doesn't use them to get to someone else. The relationship with Castle has reached a point where somebody's got to move. And if there's this guy that's really wonderful and talented and good looking, it makes sense."

Although Katic welcomes the chance to play more than just the hard-nosed police detective, she says viewers shouldn't expect to see an overly mushy Beckett. And when Beckett's new suitor becomes a suspect in the case, the two get quite physical in a steamy sparring match.

"Every woman has girly moments when they like somebody, but you've got to remember that Kate's kick-ass," she says. "I think that this romance is more like a tango than a waltz. There's some kind of primal physical attraction before anything else."

Trucco is signed on four episodes, which takes his character all the way through the finale. Katic says his character will continue to play an important role inside the precinct, but she's hoping for a romantic moment or two away from work as well.

"He's an integral part to helping solve the cases," Katic says. "I'd love for them to have a personal moment. I think he's a great character and I do hope we have that kind of a story continuing on to the next season."