Keck’s Exclusives: Castle Stages Firefly Reunion – Today’s News: Our Take | TVGuide.com
Adam Baldwin is guest starring on Castle!?!?! This news just made my night! Nathan Fillion has been great about adding Firefly nods to the show, but this tops them! It will put the two Firefly members together for the first time since Serenity. Baldwin will play Detective Ethan Slaughter, from the city’s gang unit, who lands a case Castle is desperate to follow.