TVLine broke the news on Monday that McKenna would be appearing in an upcoming episode that has a Comic-Con theme (something else Mr. Fillion is quite familiar with) and he will play Simon Westport, a super fan of Nebula9, which is the sci-fi show at the center of the episode. McKenna’s character may have been romantically involved with the victim of the case Castle and Beckett are working on.
McKenna played Joey Buchanan from 1990 to 1993 and Fillion took over the role in 1994 until 1997, returning for a guest appearance in 2007. McKenna recently guest starred on “Rizzoli & Isles”, “Harry’s Law”, “House” and “90210.” On Friday, he tweeted the above picture of himself and Fillion, saying, “Just a couple of Joeys at work.”
“Castle” airs Mondays at 10:00 p.m. EST on ABC.