This week's "Castle" is going totally film noir. In "The Blue Butterfly," Castle and Beckett discover that the murder case they're investigating is linked to a homicide from 1947 involving a lot of mystery and a very tough private detective. They soon realize that they have to crack the old case to solve the new one, and we get to see them acting out the parts in some very cool flashbacks.
Yes, it's another chance to see Castle and Beckett hooking up onscreen, without them actually hooking up (oh, those smart "Castle" writers!), but if Castle's private eye guy is really the cream in Beckett's femme fatale character's coffee as she says, why is he kissing another woman?
Check out our fun first look at this stylishly cinematic episode.
HuffPost Entertainment is your one-stop shop for celebrity news, hilarious late-night bits, industry and awards coverage and more — sent right to your inbox six days a week. Learn more