The synopsis for episode 15.
“Somewhere Between Heaven and Hell” — (8:00-9:00 p.m. ET) (Content Rating TBD) (HDTV)

THE HOUNDS OF HELL – An attack by an invisible hellhound at a campsite leads Sam (Jared Padalecki) and Dean (Jensen Ackles) to investigate the mysterious circumstances. Meanwhile, two of Crowley’s (Mark A. Sheppard) own personal demons uncover what he has been hiding. Castiel (Misha Collins) gets a lead on Kelly Kline. Directed by Nina Lopez-Corrado, the episode was written by Davy Perez. (#1215). Original airdate 3/9/2017.
A Hellhound! Demons discover Crowley's keeping Lucifer captive. Cas might find Lucifer's baby mama. Will the demons release Lucifer? What vessel is he using? I'm guessing somebody made a deal and that is why the Hellhound is out and about. Will Cas find Kelly and possibly the mysterious Dagon that we heard about tonight? Let us know what you think in the comments or in the discussion thread for episode 15.