Episode Description: Beware, spoilers! To read - hover over the text.
Wanting to get Sam's soul, Dean makes a deal with Death. It needs a day to perform the duties of Death, wearing a ring on your finger. Meanwhile, Sam, on the advice of Balthazar, trying to desecrate the vessel, killing Bobby, that soul could not exist in the body. Dean fails, but Death still descends into Hell. Dean saves Bobby and Death returns Sam's soul.