When season 11 of the CW series "Supernatural" premieres on 7 October, we will see the havoc that "Darkness" wreaks in the world.

Darkness is something so unfamiliar to the Winchesters; they will need all the help they can get. One popular plot theory for the upcoming season, therefore, is that they recruit old friends and enemies to counter this evil.

Darkness has been mentioned in the finale episode of "Supernatural" season 10 only once. By removing the Mark of Cain from his forearm, Dean (Jensen Ackles) let out Darkness from its prison, and now, like every other mess the Winchesters make, they have no idea how to reverse it.

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Darkness is said to be older than hell itself, and with Castiel (Misha Collins) under the spell of Rowena (Ruth Connell), the brothers need more help than they have ever needed. It is believed that God would appear to the Winchesters and help them in putting Darkness back in its prison.

Before God, there was only darkness within existence, Death (Julian Richings) had said before Dean killed him. Since the primordial being is older than him, in all probability Darkness can kill God, which is also supported by Death's remark that God took the aid of all his archangels in the war against Darkness.

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If that is the case, then God, who has been in hiding, and has not answered the calls of any of his children – angel or human – might return. Rob Benedict who played Chuck aka God in Season 5 of "Supernatural" was present at the show's panel at Comic Con, and kept not-so-subtly hinting that he would want to come back. We can assume it would be a reality soon.

He co-hosted the panel with Richard Speight Jr., who played Garbiel aka The Trickster and one of the archangels. Although he was shown dead in season 5, and the dead status was later confirmed in Season 9, we all know the Trickster is good at tricking people into believing he is dead.

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The theory is that Gabriel will lend his support to the Winchesters yet again, in an attempt to defeat Darkness, at the behest of his father, God. He will break his brothers Michael and Lucifer out of prison and they will all work together with Sam (Jared Padelecki) and Dean to save the world from the unknown force.

Come back here for more updates, fan theories and speculations on "Supernatural".