Following a meeting with their temporally time-displaced grandfather, [[Henry Winchester]], Dean and Sam take custody of the archive of the [[Men of Letters]], an organization dedicated to recording the supernatural before their destruction in the 1950s. With the archive resources and Kevin's translation of the tablet, Sam sets out to complete the three trials to seal the Gates of Hell, which include killing a [[hellhound]], delivering an innocent soul ([[Bobby]]) from [[Hell]] unto to Heaven, and curing a [[demon]]. However, Dean stops Sam when he learns that the trials will kill him, shortly before renegade angel [[Metatron]] seals off [[Heaven]] using spell to banish all the angels from Heaven and leaving Castiel human.
[[File:DemonDean.png|thumb|right|350px|Dean is revived as a [[
===[[:Category:Season 9|Season 9]]===
In order to save Sam's life, Dean manages to make contact with a fallen angel who introduces himself as '[[Gadreel|Ezekiel]]', who manages to trick Sam into agreeing to act as his [[Vessel]] while in his coma, allowing Ezekiel to heal Sam's injuries and recharge his own 'batteries' from inside Sam. With Castiel reduced to a human state and on the run from the other angels, Dean orders him to stay away so that Ezekiel can focus his energies on healing Sam while [[Kevin Tran]] studies the [[angel tablet]] to find a means of reversing Metatron's spell. However, things become more dangerous when the fallen angels begin to fight amongst themselves and [[Abaddon]] sets out to take over Hell while the Winchesters hold [[Crowley]] captive.