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Peggy Olson (Elisabeth Moss) started out as a secretary, spending her days typing and fending off unwanted advances. But by the middle of season 1, she was penning ads for Belle Jolie lipstick — and not long after that, she was officially promoted to Junior Copywriter. As season 6 begins, Peggy has left SCDP behind to become Cutler Gleason and Chaough's Copy Chief. Her trailblazing would pave the way for Megan Draper (Jessica Paré), née Calvet, who eventually became SCDP's second female writer. (Though in Megan's case, marrying the boss didn't hurt).
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Guess Who's Coming to Sterling Cooper
Paul Kinsey (Michael Gladis) fancied himself an iconoclast — so it's no surprise that he was the first character on Mad Men to date across the color line. What's more, Paul's relationship with Sheila (Donielle Artise) was more than a fling; it lasted for almost an entire season, until Sheila realized Paul's heart wasn't really in the whole civil rights thing. Later, Lane Pryce (Jared Harris) would briefly date a black woman as well.
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I'm Coming Out
Poor, closeted Sal (Bryan Batt) never embraced his homosexuality on the show. But a younger generation apparently doesn't have the same hang-ups. In season 2, strapping German ad man Kurt (Edin Gali) casually announced that he ''make[s] love with the man, not the woman.'' And in season 4, Peggy met Joyce Ramsay (Zosia Mamet, who's currently starring on Girls), an openly gay photographer. Now, if only we could get Sal back...
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The Straight Dope
When Don Draper's (Jon Hamm) bohemian mistress (Rosemarie DeWitt) offered him a joint in season 1, the show implied that marijuana was illicit and dangerous. By season 3, Peggy and Paul were smoking up in their office — and these days, drugs other than alcohol show up regularly on the series. The latest and greatest example: Roger Sterling's psychedelic acid trips. The saddest one: Don discovering his old flame is addicted to heroin.
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Between three-martini lunches and booze-soaked client dinners, most of the Mad Men themselves are functioning alcoholics. But in season 4, the oft-inebriated Freddy Rumsen (Joel Murray) reemerged after a long absence — and this time, he was totally clean and sober. Eventually, Freddy revealed to Peggy that he had become a member of Alcoholics Anonymous. Though Duck Phillips (Mark Moses) was also an admitted alcoholic, Freddy's the first character we saw successfully kick his addiction.
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Sterling Cooper Draper Pryce was literally built on the back of Lucky Strike Cigarettes. But in late season 4, SCDP learned that its biggest client was leaving for another agency — and Don responded by declaring, in writing, that SCDP would never again peddle a product ''that causes illness, and makes people unhappy.'' Sure, his reasoning wasn't exactly altruistic — but rejecting cigarettes ostensibly on behalf of public health is a huge deal on this smoke-filled show.
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The New Girl
In season 5's premiere, SCDP's partners found themselves in a bind when an ad they had placed as a joke drew hordes of African-American job applicants. They ended up hiring Dawn Chambers (Teyonah Parris), the agency's first black employee — and, more broadly, the first character of color who's not a housekeeper, a janitor, a waiter, a grocery store check-out girl, or an elevator operator. Next up: a black copywriter?
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Gaining a Religion
From the very beginning, Mad Men's offices have been chock-full of anti-Semitism — despite the fact that several characters, including Jane Sterling (Peyton List) and Faye Miller (Cara Buono), are Jewish. Now the talented young Michael Ginsberg (Ben Feldman) has joined SCDP's copy staff. While he isn't the firm's first Jewish writer — that'd be Danny Siegel (Danny Strong) — he's certainly its most openly, emphatically Jewish employee. Let's hope his stereotypical father doesn't show up again, though.
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Single White Female
Joan Harris (Christina Hendricks) realized early on that her fiancé Greg (Sam Page) was bad news. Unfortunately, she married him anyway — and after having a child, it seemed like she'd be stuck with Greg forever. (Never mind that the baby isn't his.) But this season, Joan finally found the strength to tell Greg to get lost. Now she's Mad Men's first single working mother, not counting a peripheral character from season 1. Will she convince SCDP to build a daycare?
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They've Got the Blues
Several members of the Draper family have had brushes with mental illness: Betty (January Jones) discussed ''the problem that has no name'' with a psychiatrist in season 1, Don battled an undiagnosed depression in season 4, and Sally (Kiernan Shipka) was sent to a child psychiatrist after acting out that same year. But there's been some progress in the way those issues have been treated: While Betty's psychiatrist was largely unresponsive and unhelpful — not to mention a spy for Don — Sally's doctor was sympathetic and empathetic. And in season 5, we met Beth Dawes (Alexis Bledel, above), a depressed housewife whose own depression is treated with electroshock therapy. The catch: Though it wrecks her memory, the treatment works.
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What a long, strange trip it's been! In season 1, Peggy dressed like a bobby soxer and did The Twist with abandon; by season 5, she was rocking mid-decade helmet hair and pitching ads based on A Hard Day's Night. (Don, naturally, doesn't get the music that's sweeping the nation and rejects The Beatles' ''Tomorrow Never Knows'' after just a few moments.) The most striking example of a character getting swept up in a cultural fad, though, had to be Paul's sudden reemergence as a member of the Hare Krishna movement. He's certainly come a long way from the Princeton Tiger Tones.