For years, fans have wanted Jeffrey Dean Morgan toreprise his role as John WinchesteronSupernatural.
After all, he had a lot ofunfinished business with his sons, Sam and Dean.
(Thanks for that, Amara.)

Dean Buscher/The CW
So now, John and Mary get to havethe reunionneither of them ever thought was possible.
ENTERTAINMENT WEEKLY: What was your reaction to reading the 300th episode script?SAMANTHA SMITH:I gasped.
It has the built-inSupernaturaltragic element to it.
So this moment is going to set her back is my guess.
I have a feeling shes going to take a hit from this.
The last time we saw you and Jeffrey Dean Morgan together was the pilot.
I call her Nightgown Mary.
Except for the one appearance where she was hallucinations where she could be mean and when she was Eve.
But Mary was always this particular thing.
I love where shes come.
I love Mary, all of her, even her foibles.
Its tremendous fun trying to keep up with her.
And John only knows Mary from before so she gets to be that in that moment.
How do you describe the moment when she first sees John?Its very romantic.
Its a very romantic, simple moment.
Thats whats great about this whole reunion of the family its pretty simple so it can go deep.