From mocking this generations most useless celebrity to going back in time to another generation...
Castle will take this Monday off and then return on February 6 with an especially fun, unique episode titled "The Blue Butterfly."
On the installment, look for Castle and Beckett to discover a connection between the killing of a treasure hunter and a homicide from 1947... which, naturally, will cause Castle to imagine himself during that era in order to solve the present-day case.
Ever imagine what Castle might look like as a private eye? Or Beckett as a femme fatale? Watch the official ABC promo now: