What if supernatural ends with God granting Sam and Dean a do over for their lives without hunting and the supernatural, so he claps his hands and then suddenly every bad thing that ever happened to them didn’t happen?
We flash back to that night all those years ago: “The Road That Should Have Been,” and instead of Azazel being the one at Sam’s crib, it’s John and he’s kissing the boy good night.
Then we get a montage of every good thing that happened in their lives. Dean and Sam both went to college. Sam for law, Dean for engineering. We see Sam’s wedding, where Dean is the best man. We see John and Mary as elderly adults.
The we stop at a super market, years later. Sam and Dean are the same age they are now. We hear Sam call a little boy, John, named after their loving father running up to Jess and Sam.
"Dean, hurry up, John’s ready to go!" Sam would call, and Jess would roll her eyes, because she knows that Dean is trying to find a slice of apple pie at that damned deli.
So, the camera pans over, and we see Dean surveying the deli for some apple pie, only to sigh sadly when he realizes that they only have cake. “Is something the matter?” A deep voice asks, and Dean jumps and the camera moves back to show a dark haired, blue eyes man in trench coat standing behind of Dean.
"Um, no pie." Dean replied, as he moved to scratch his neck. He looks down at surveys the man, because damn. “The name’s Dean, Dean Winchester.” The camera is now between the two, both looking at each other intently, almost like they are old friends meeting after years.
"Hello Dean." Castiel replies, and then he hold out his hand and takes Dean. We hear Sam still calling Dean in the background, and then the screen goes black.