Where's Joan when we need her? She's been gone a scant week and Sterling Cooper is falling to pieces without her. Don takes drugs. Peggy sleeps with the enemy. Mr. Cooper resorts to blackmail. And Joan isn't even mentioned once!

Of course she'll come back. "Mad Men," which won the Emmy for best dramatic television series last week, just isn't the same without her. If you don't know who Joan is, you don't watch this smart, quirky show on AMC Sunday nights. Sharing its glories, dissecting its most recent plot turns and assessing the characters' character almost takes the sting out of Monday mornings.

Sure we love Don Draper, the handsome ad agency creative director who is married to Betty, the former model turned bored housewife. We root for Peggy as she tries to transform herself, and we like Pete even though we don't. Roger's a transparent cad but not without a certain charm, and we pray that Salvatore will come out of the closet. We could go on, but the point is Joan.

As played by Christina Hendricks, she has grown from the peripheral character of office manager into one of the show's stars, with a cult following that's rather astonishing. The typical take on Joan is that she inhabits the middle ground between Betty, the archetypal '60s suburban wife and mother, and Peggy, the emancipated working woman. But to dismiss Joan's character with such ease would be to deny the impact she's had on contemporary culture.

There's a Web site called WhatWouldJoanDo.tumblr.com, a sort of Dear Abby that adopts Joan's attitude as it gives advice. Joan is all over Jezebel.com, Twitter and a million blogs. She's being championed on the runway with the re-emergence of the sheath dress, her weapon of choice. No one could wear it better (except maybe Queen of Sheath Carla Bruni!), and the much-touted fashion influence exerted by "Mad Men" has settled around Joan, whose voluptuous figure is displayed to great advantage in a parade of chic dresses.

"She may be the sexiest woman on television," offers a colleague at the Post-Gazette. When the agency is planning a new campaign for Playtex, they divide the women in the office into two categories -- Jackies and Marilyns. Except for Joan, who gives them pause. "Well, Marilyn's really a Joan, not the other way around," notes Paul Kinsey.

But Joan's physical appeal is only part of her allure. Take episode six. We know the moment the John Deere riding mower enters Sterling Cooper that nothing good will come of it. But the gruesome accident that ensues is a surprise. What isn't is the way Joan reacts. While the staff stands frozen in horror, only Joan rushes to aid Guy, the new boss who lies writhing in pain, calmly placing a tourniquet above his severed foot. Something she learned in Red Cross class in high school, she demurs.

"What can't Joan do? Joan is the woman!" offers another Post-Gazette colleague, one of the many female fans who responded to an informal office survey: Joan or Betty?

More intelligent than most of her bosses, more worldly, observant, sensitive and funny, Joan is the soul of discretion, knows how to enforce boundaries and is well-versed in the politics of life. That so many women relate to Joan (and none to Betty!) is the major reason for her success. She's the most contemporary of characters, a modern woman in a very real sense of the word.

Joan embodies where women are today -- a 360-degree turn from where they were in 1960. Now that we've had independence, now that we're expected to work and have careers, we're torn. The other side of womenhood hasn't gone away -- we're still assuming primary responsibility for creating a family life, only with a lot more guilt. Like Joan, we want both.

To be a viable player in the workforce and a stay-at-home mom. We sympathize with Joan, whose dream of marrying well and retiring into pampered wifedom has clearly been sabotaged by her choice of a husband. Dr. Greg Harris fits all the criteria on the surface, but underneath he's weak, whiney and abusive. He doesn't deserve Joan, and we want her to realize that. When she comes back, the question won't be what would Joan do, but what will she do? Stay tuned ...

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