"Mad Men" is a deeply philosophical, introspective show that focuses on characters who all deal with some sort of isolation or loneliness. For Betty, it's the isolation of being a '60s housewife. For Don, it's the loneliness of nobody around him knowing who he truly is. For Peggy, it's being one of the only women in a male-dominated field rampant with sexism. With work-focused characters struggling so much just to not feel alone in the world, the relationships between the employees of Sterling Cooper are some of the strongest points on the show.

One relationship that sits at the very heart of the show is that between Don and Peggy, played by Jon Hamm and Elisabeth Moss respectively. What begins as a simple employer/employee relationship evolves into that of a surprisingly close mentor/mentee. Don is one of the first men in their workplace to believe in Peggy's ability as a copywriter and becomes a major influence on her professional life. Peggy is aware of Don's personal coldness, but still holds a fondness for the man who helped her out at times when nobody else would.

According to a Vanity Fair interview with Moss, the close relationship between Don and Peggy extended beyond the screen. Moss and Hamm's real-life relationship was also that of a mentor and a mentee, and they utilized their real-life feelings for one another to invigorate their greatest scenes together.

'It All Felt Very Real'

In the Vanity Fair interview, Elisabeth Moss reflects on one of the most pivotal scenes in the relationship between Peggy and Don, when Peggy decides she'll be moving on to another agency. In a moment where a visibly terrified Peggy is afraid that announcing her departure will be received with the anger Don is prone to, he responds with a surprising amount of tenderness, kissing her hand gently while tears well up in her eyes. According to Moss, filming this scene meant a lot to both actors:

"It all felt very real. I have a very close relationship with Jon [Hamm]. There was sort of like a mentor/protege relationship there, very older brother/little sister. And so it meant something to the both of us when we did this scene … Those are real tears … because he held onto my hand and didn't let go and then kissed it. None of that was in the script, and he did it on my close up. Like, that right there is the real Jon."

In a scene where Don quietly accepts the fact that his student is moving on, and that he'd no longer be working with her day in and day out, there's a clear reflection of their real-life relationship. While Moss wouldn't actually be leaving the show, Hamm was still clearly proud of the work and growth they'd done together. And now they'd be scene partners less often, which would be sad for Hamm, who was nervous acting for most of the run of "Mad Men." But beneath all of that, Hamm is proud of Moss, just as Don is of Peggy.

Rare Respect

While Don goes through a plethora of different romantic entanglements on "Mad Men," it's his relationship with Peggy that serves as his anchor on the show. Even at the end of the series, when Don has disappeared to California and most people have written him off, Peggy is one of the three people Don calls, along with his daughter and his dying ex-wife. To him, Peggy was clearly one of the three most important people in his life.

While it's hard to say whether there was any actual love between the two characters, whose relationship was often strained by the stresses of work, there was something that came very close and indeed sometimes acted as a substitute for the love they often lacked in their personal lives. In a TV Insider interview from 2015, Jon Hamm reflected on the nature of the relationship between the two characters:

"It's a relationship that started severely unequal and has moved, in a certain way, to equals. It's not love, I don't know what it is, but it's some other thing, even though, at a lot of times, he is dismissive of it, it's the one relationship I feel like Don actually treats with respect."

It's this respect that Don rarely doles out freely that elevates his relationship with Peggy above many others. Don's a cynical man who doesn't believe in much, but he believed in Peggy, even if just in a professional capacity. And this belief in Peggy's ability is similar to Hamm's belief in Moss.

Their Relationship Is More Than That

For a character like Don, who's a serial womanizer to a self-destructive level, having any non-sexual relationship with a woman is quite unusual. And much like Jon Hamm and Elisabeth Moss' real-life relationship during the making of "Man Men" (rumors aside), Don and Peggy's connection never becomes romantic.

Both Hamm and Moss have agreed that's a hugely important aspect of their characters' relationship, and part of why it's so interesting. "People are constantly asking if they're gonna sleep together," said Moss, speaking to Vulture in 2012. "I always get annoyed, because their relationship is more than that."

"People want to put us in a 'Sam and Diane' box, but it's about their mutual appreciation for the work," added Hamm. "That's where the material strikes its resonant chord, when it's ostensibly about one thing and then it becomes about so much more."

Just like Don and Peggy, Hamm and Moss bonded partially through a mutual appreciation of each other's work — one that became a lasting friendship they cherish to this day over the eight year run of "Mad Men." It's this mutual respect and love that allowed both performers to bring genuine emotion and heart to all of their shared scenes.

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