THEN: Lilith wanted to break the 66 Seals to bring Lucifer to Earth. Dean was recruited by the angels to stop it while Sam went his own route, drinking demon blood until he became strong enough to defeat her. This difference in strategy caused the brothers to have an epic fight and vow never to speak to each other again.
NOW (actually, still THEN, since the opening scene takes place in 1972): At a Maryland convent in 1972, a priest is terrified when a demon rushes in and takes over his body. The next day the priest fives a sermon to the nuns that his dad is locked away and that, ironically, he recently learned that the door to his cage is at that very convent. The demon priest yells at the nuns and then his eyes goes Yellow before he has some fun. That's right...Azazel is Lucifer's son!
Ruby and Sam stop on the side of the road. Ruby thinks Dean was wrong to say what he said, but Sam actually agrees with him. There's something evil inside of him and Sam realizes what he has to do and he knows Dean is better off without him.
The camera cuts to Dean in a mirror image of Sam's face when they first showed him. Dean is feeling sorry for himself. He claims Sam never wanted this and that he's glad Sam's gone. Uncle Bobby gets fed up with their childish crap and turns on the tough love. He yells at Dean telling him that family isn't supposed to make you feel good and he should stop being such a whiny brat. You tell him, Bobby!
To Read More Click Here.