Where Sam's mind is shaky after Castiel breaks down the Wall, the cold is suddenly the enemy, and Dean is struggling to keep up with it all.
Also, Lucifer's trying to fix the world the humans broke.
Sam has been having nightmares of Lucifer and he doesn't know how to tell Dean and Gabriel an Castiel, so he doesn't. until one day when they hear a knock on the door and Sam opens it to reveal Lucifer.
I wonder how things will pan out °^°
My grammar sucks I'm the first few sorry :/