The WInchester boys are mourning the losses of Castiel and their mother while they try and track down Jack, a.k.a. the nephilim son of Lucifer and Kelly.
Supernatural is the CW series that just keeps on going, and it has officially returned for Season 13.
The episode was surprisingly somber and mournful for a Supernatural premiere, which are usually more high-octane.
Given what happened in the Season 12 finale, however, the more somber tone was just right.