Who is CASTLE Kissing in These New Photos?

Well this ought to get Castle fans riled up! In new photos for the episode airing October 17, “Eye of the Beholder”, Beckett comes upon Castle kissing another woman. Wha…?!? Don’t worry, ABC wouldn’t have revealed this so early before the episode aired if it were real. Take a look at that body language: I’m guessing Castle is up to something that has less to do with being interested in the woman in red (Serena, a smart, sexy insurance investigator working on a case with Castle & Beckett) and more to do with, I don’t know, making Kate jealous?

Here’s the full photos set, courtesy of ABC.