Underappreciated Moments → Dean’s role in Swan Song.
Now, this scene in Swan Song isn’t exactly the first thing that comes to mind when you think of “underappreciated moments.” I’ve seen a million posts about how Sam sacrificed himself to save the world, how he defeated Satan because of his love for Dean, etc. Hell, I probably wrote half those posts myself. But I haven’t actually seen a whole lot of posts about Dean’s role in this scene, and that’s what I’m gonna talk about right now.
Picture it in your mind: Dean driving alone to the cemetery, a look of complete determination on his face. He gets out of the car. He sees his two brothers - one, practically a stranger; the other, everything in this world that he knows - standing there, facing each other. Michael and Lucifer. Two incredibly powerful angels that have been around since literally the beginning of time.
Without a single moment of hesitation, Dean walks towards them and demands to speak to Sam. This is huge all on its own: Dean has no doubt, absolutely no doubt, that Sam isn’t completely lost. To Michael, he says: “Adam, if you’re in there somewhere, I am so sorry.” To Lucifer, he says, “I’m talking to Sam.”
Anyway, we know how this goes…now fast forward to the part where Lucifer!Sam is beating the shit out of Dean up against the Impala. Dean is covered in blood, half-unconscious. He just keeps repeating over and over, like a prayer to something he believes in more than any god: “Sammy, it’s okay. I’m here. I’m here. I’m not gonna leave you.”
He doesn’t fight back, or run away. He never even tries. He just lies there and takes it.
Castiel: The only thing you’re going to see out there is Michael killing your brother.
Dean: Well then, I ain’t gonna let him die alone.
And I’m compelled to quote the echo a year later: Sam:I’m not gonna leave my brother out there alone.