Dean took a long drink of the whiskey before placing the cup down and looking back at her. "Apparently the four rings of the horsemen are the keys to Lucifer's cage. Know the right incantation, and you pretty much open the door to Hell. The next step in the plan was getting Lucifer to go in. Sam figured if he said yes and managed to beat him down, then jumped right in, the doors would close and Lucifer would be back where he belonged. So we went to Detroit."

He swallowed again before continuing. "It didn't go too well at first. Lucifer got the upper hand and things almost went pear-shaped but Sam got a handle on it. He beat Lucifer down, opened the gate and when Michael tried to stop him, he yanked him back in with him."