10x21Dark Dynasty Episode Summary Aired: Wednesday May 6, 2015
Dean and Sam investigate a bizarre murder and realize the killer bears the same tattoo as those from the Styne family. Eldon Styne attacks Dean and a brutal fight ensues. Meanwhile, Castiel acts as referee when Charlie and Rowena are forced to work together on the Book of the Damned. Crowley discovers his mother is missing and knows she's up to something so he turns to an old enemy for help.