Here's the truth: I'm genuinely both worried and excited about Season 11 of Supernatural . As all fans know, when we last left our beautiful Winchester brothers — and the rest of the equally beautiful Team Free Will + Rowena — Dean attempted to get Death to remove the Mark of Cain (which he wouldn't), kill him (which he couldn't), or whisk Dean away so he would no longer do anyone harm. Death gave Dean the third option, but at a cost: He would have to kill Sam first to ensure Dean would not be found and the Mark would not be removed, because removing it meant releasing the Darkness which had been kept locked away in the Mark since the time of God and Lucifer (before Season 5, guys, we're talking the Bible ages here). But Rowena, Crowley, and Castiel succeeded in removing the Mark, as Dean potentially killed Death with Death's own scythe. Then The Darkness was released and came rushing at the boys. Now the questions remain: what is the Darkness and why is everyone so afraid of it?
Now can you see why I'm so excited and nervous for the new season? Things are looking more grim than ever before, and that means Supernatural must find a way to execute a concept highly anticipated by an eager, rabid, diehard fanbase (I include myself in this). We don't want a repeat of the Leviathans storyline, which was so great in theory but completely lost in translation. So I have a few theories about what this "Darkness" could mean for the Winchesters and the rest of the world.
1. Hell On Earth
This semi-obvious (slightly redundant) theory is that the black mist, aka The Darkness, that came out of the Earth, formed together, and then exploded onto the lands could be something we've seen before: Demons. Death spoke about how The Darkness had been locked away in the Mark of Cain by God, who gave it to Lucifer after being tricked, who then gave it to Dean. What if that locked away Darkness could actually permeate through people and their souls? Maybe now it's unlocked the gates of Hell completely, bringing forth the truly dark demons out of their prisons and unleashing them onto the world.
Dean and Sam would face once again the problem they had in Season 2 when a gateway to Hell was opened, but on a much more epic, worldwide scale. While this would definitely be a bit of a bummer considering we've already seen this happen, it could be interesting because the Winchesters would have to deal with the realization that their efforts have been for nothing. Plus, Sam will feel guilty he didn't close the gates of Hell when he had the chance, despite almost dying in the process.
2. It Will Bring About Chaos
As I've stated before, it's possible that the Darkness will just be a manifestation of the Mark of Cain, but brought out in every person who is infected by it. As it spreads out through the world, more and more people could be affected by the Darkness as their evil sides come out. It's basically like a re-imagining of the Croatoan virus, except a ton of people would begin acting the way Dean had been all season long. If this is the case, how does one stop the Darkness?
And if Dean really killed Death, does that mean that people won't die or that someone else takes over as Death, like Dean himself? Seeing Dean Winchester as a reaper trying to handle his new job in the midst of chaos? That could be interesting to watch.
3. It's A New Apocalypse
Honestly, this storyline (or a variation of it) is the one I would most like to see on Supernatural next season. Perhaps when the Darkness was released into the world, it triggered an apocalyptic event once again, and only Lucifer and Michael can stop it... Which would mean they have to be sprung from the cage in which Dean and Sam locked them. Unlike in Season 5, however, the Winchesters now must accept that they are the true vessels for the angels and sacrifice themselves for the good of mankind.
Unfortunately, this would basically mean the end of the series (unless they were pulled out of the cage like Sam was), but it would be quite the poetic way to go. The Winchesters would die knowing they finally saved the world from disaster, erasing the guilt they feel (especially Dean) over all the damage they've done. Plus, we could see the return of Adam and Chuck (!!) and possibly a ghost version of Gabriel. Maybe John could even return? Obviously I don't want to see Supernatural come to an end, but I'd be totally fine with this kind of finale.
There is a ton of potential for a storyline so expansive, completely drenched with epic Biblical components, and chock full of more dark, deep human emotions from both Winchesters. I can't wait to see what current showrunner Jeremy Carver and gang do with the Darkness. But no matter where the Supernatural writers take, I just hope they make good on the promise that Season 11 will be darker than ever. Do your worst — we're ready.