The eighth season ends with Crowley poised to undo all of the good that Sam and Dean have accomplished as hunters. But the Winchester brothers try one final play against the Demon King. Meanwhile, Metatron gets Castiel to help him take on Naomi and the bureaucracy of heaven.
When Dean and Sam receive an upsetting video message from Kevin, they decide to try and uncover the third trial; Castiel tries to get away from Naomi and the angels.
Dean asks Sam to stop hunting until he recovers from the second trial; when a hacker (Felicia Day) stumbles upon a case, Dean teaches her how to be a hunter.
Sam and Dean team with a reaper to help them deal with the second trial from the Tablet. Meanwhile, Naomi visits Dean, and he realizes he must find Benny and ask for a huge favor.
Castiel tells Dean and Sam that Crowley has unleashed multiple demons in a small town; during an interrogation, the guys learn that Crowley has been torturing Meg.
A cop who practices witchcraft is plagued by nightmares in which he kills innocent people. When the murders actually happen, Sam and Dean are called in to investigate.
Kevin figures out how to close the gates of hell after deciphering the tablets; Sam and Dean argue over who should complete three trials designed by God.