fillion firefly castleLast night's Halloween-themed episode of Castle, starring a spry as ever Nathan Fillion, featured a few surprise winks to Joss Whedon and Firefly fans. Not only was Buffy referenced in an episode involving vampires and werewolves, but Fillion even dusted off the ol' brown coat and boots to dress up like Firefly's Captain Mal Reynolds.

The get-up was part of novelist/detective Frank Castle's "space cowboy" costume, but those of us who attend Serenity midnight showings on a regular basis know that Fillion and the show were giving a huge shout out to Firefly fans.

Head after the jump for a clip of Fillion reliving his Alliance-fighting glory days on Castle. And, yeah, we really, really miss Firefly too.