The gruesome death of a mystery man dressed as a prisoner led Castle to take on the role of college professor, including the tweed jacket and glasses in Castle Season 8 Episode 3.
As Alexis and Martha put together the Castle Depression Rescue Kit, Rick picked himself up and decided to go and win his wife back by solving a case.
Little did he know that Beckett had her own reasons for walking out of the loft.
Will Castle solve the case? Will Kate Beckett come home? Want to find out? You can watch Castle online here at TV Fanatic.
C. Orlando is a TV Fanatic Staff Writer. Follow her on Twitter.