In their Schedule announcement, The CW released the Description of Supernatural Season 6.
Massive spoilers of the season six ahead:
(from The CW’s press release, May 2010)
Returning for its sixth season, this haunting series follows Sam and Dean Winchester, two brothers bound by tragedy and blood to their dangerous, other-worldly mission. This past season, Dean and Sam faced their toughest foe yet: the Devil himself… As the Apocalypse raged on around them, the brothers, aided only by a dwindling band of fellow hunters and rebel angel Castiel, sought a way to stop Lucifer and save the planet. Ultimately, they discovered a way to force Lucifer back into Hell and end the Apocalypse – but at tremendous cost: Sam’s life. Season six will be a season of mystery and shadow. Heaven and Hell have been left in complete disarray since the apocalyptic events of season five. And now, monsters, angels and demons roam across a lawless and chaotic landscape. And so Dean Winchester, who has retired from hunting and sworn never to return, finds himself being pulled back into his old life – pulled back by none other than Sam Winchester, who has escaped from Hell. The two reunite to beat back the rising tide of creatures and demon-spawn, but they quickly realize that neither are who they used to be, their relationship isn’t what it used to be, and that nothing is what it seems.
SUPERNATURAL is from Warner Bros. Television in association with Wonderland Sound and Vision, with executive producers McG (“Nikita,” “Charlie’s Angels,” “The O.C.”), Eric Kripke (“Boogeyman”), Robert Singer (“Midnight Caller”), Sera Gamble, Ben Edlund and Phil Sgriccia.