So, the IC is up, now.  

For TL;DR reasons, I will summarize what is going on for your characters world right now.

Sam Winchester died.  Dean Winchester made a deal with a demon to save Sam, but the demon could have his soul in one year.  That year passed.  The demon, Lilith, came with her hellhounds and took Dean to hell.  They ripped him to shreds.  After a long stay in hell (4 months earth time), Dean has risen from the grave, being dragged out by an Angel of the Lord.

That's where we are, now.  I decided not to do Season 3, only because it's so short...and half the season is full of filler episodes.  So, we are getting right down to the meat of the apocalypse and starting with season 4, episode 1.