In its early seasons, Mad Men sometimes felt like two different shows. One was about a handsome, mysterious ad man who dominated Madison Avenue with a series of perfect pitches. The other was about a pathological adulterer whose marriage was falling apart.

Don's repeated personal failures are now very much affecting his professional life. Sunday night's "The Strategy" found him in the office, reeling from a morning in which his wife was literally collecting more pieces of her life to move thousands of miles away from him. For Don, the lines between work and family have become impossibly muddled — and when he chose the chance to rebuild his career at Sterling Cooper over the chance to move to Los Angeles with Megan, he probably lost her forever.

It's been a similarly rough season for Peggy Olsen, who has been forced to choose between her personal life and her professional aspirations from the very beginning. She lives alone, and is constantly being pestered by her demanding renters. Her boss, Lou Avery, is a hack who lacks dedication. Peggy is underestimated and ignored by most of her superiors. And in last week's "The Runaways," she was unknowingly drawn into Ginsberg's mental illness, which culminated in him severing his own nipple and giving it to her in the office.

And now, in "The Strategy," she finds that all her hard, careful work on the Burger Chef account will be passed off to Don Draper in the eleventh hour, if only because Pete Campbell's man-crush on Don remains as strong as ever. Don is a genuinely talented creative mind, but he's not replacing Peggy as the lead Burger Chef pitcher because she's incapable of delivering the idea in a compelling way; he's doing it because Pete wants him to play "Don Draper," the dashing, brilliant ad man who the real Don works so hard to be. "Don will give authority, and you will give emotion," suggests Pete. "I have authority and he has emotions," replies Peggy.

But the truth, for both characters, lies somewhere in between. By now, most of Mad Men's characters have spent enough time with Don to realize that he's not all he seems to be. Don's humbling leave of absence after last year's ill-fated Hershey's pitch knocked him down a few pegs in the office, and his wives and his children have been confronted with evidence of his deeper and more honest flaws. But for all his slip-ups, there are only two people who understand just how constructed "Don Draper" is: Peggy Olsen and Don Draper. "The timbre of my voice is as important as the content," said Don last year, in a rare moment of professional honesty. It's a charge that Peggy echoes in "The Strategy" as she grumbles to Don about the well-worn formula of pitch he'll be delivering to Burger Chef: "And then you turn and give the tag like you just thought of it."

But for all the tensions they've had this season, Don and Peggy's bond remains the backbone of Mad Men, and "The Strategy" features the most powerful depiction of their relationship since season four's series-best episode "The Suitcase." Mad Men began as Peggy took over as Don's secretary, and went through its first seismic shift when Don gave her the chance to write some copy. In the years since, they've seen each other during their most vulnerable moments: Peggy, after giving birth to Pete Campbell's child and giving it away, and Don, as he broke down in miserable sobs after Anna Draper's death. As Don lamented the death of the only person who really knew him, Peggy gently reminded him that that wasn't true.

Don and Peggy's intimacy surpasses the romantic, and Mad Men wisely shut down the possibility of anything happening between them by the end of its first episode. Their gentle, wordless dance to Frank Sinatra's "My Way" will undoubtedly figure into a thousand fan-fiction scenarios to come, but Don and Peggy's connection goes deeper than physical attraction. It's a shared worldview that makes them different than anyone else around them — including the people they love. As usual Don's advice about advertising also hints at the difficult crossroads they've both reached in their lives. "I want you to feel good about what you're doing, but you'll never know," he says. "You can't tell people what they want. It has to be what you want."

What do Don and Peggy want? Only by spending the evening together do they discover the real answer: family. Burger Chef isn't a place where a harried mother picks up a desperate, last-minute meal; it's the dining room of the next generation, where all kinds of families will come together to enjoy each other's company without the distractions of the rest of their lives. "It's a clean, well lighted place," says Peggy as she sits down with Don and Pete. "It's about family. Every table here is the family table." Don, Peggy, and Pete's lives are in utter upheaval, and there may be a lot more heartache to come — but for one brief moment, the troubled, damaged trio at the heart of Mad Men is a happy family.

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