'Mad Men' Costume Designer on Jessica Pare's 'Zou Bisou' Minidress and Black Lace Lingerie

Ron Jaffe/AMC

Janie Bryant helped Megan Draper replace Betty Draper as the most stylish, exciting woman on the hit AMC drama.

It’s unclear who was more shocked when Megan Draper (Jessica Pare) – in a sexy black minidress -- performed “Zou Bisou” during the Season 5 premiere of Mad Men: The viewing audience, the guests at Don Draper's surprise birthday party or her onscreen husband (Jon Hamm).

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But there was more to come. The next day, Don comes home to find an annoyed Megan in a bright pink and orange dressing gown. Suddenly, she strips to her black lace underwear and gets down on all fours to scrub the floor, telling him,”You don’t get to have this. Go sit over there. All you get to do is watch. “

If you watched, you know that’s not all he got to do. And in that instant, the new Mrs. Draper forever replaced the old Mrs. Betty Draper, (January Jones) as the formidable woman to watch on the series this season.

The Hollywood Reporter went straight to the style source, the show's award-winning costume designer Janie Bryant, to find out what Megan's clothing -- even her lingerie -- says about this little seductive minx who bosses Don Draper around (and he seems to  like it).

“I always saw Megan as a character who is young and fresh, on the pulse of what was happening in the youth culture, more than any of the other women on the show. Her wardrobe really reflects that transition into the mod period of the ‘60s.  Also, she’s an actress and she's from Montreal so those are different elements of her character."

It’s already clear to fans of the show that Megan is the most fashion forward, with a bit of an international edge to her outfits. Of all the women, she’s the one we think would subscribe to Vogue.

For Megan's surprise "Zoo Bisou" performance, Bryant chose a vintage black dress with rhinestone embellishment around the neck. She remade the original tattered sleeves out of pleated silk chiffon.

“It was all about the sleeves,” she says. “I knew she would be singing a song and I knew that she would dance and I talked with Matt [Weiner] about how it would be choreographed. So it was about the arms and also the legs, because this was when the miniskirts were invented. Actually, I just read that Courreges invented them and it was Mary Quant who made them popular. There is always that battle going on between designers."

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Bryant chose a classic black dress because, “There is nothing sexier than a little black dress and to me that speaks to the French flair of her character." It also makes her stand out and look sophisticated amid the brightly colored and patterned dresses worn by the other women at the party.

Did Jessica  have to rehearse wearing the dress? “No, but she rehearsed with the shoes,” Bryant says. “They were square-toed, square-heeled, vintage, about 1 ½ inches high. Very mod.”

The dressing gown is one of her favorites in the episode, a vibrant vintage 60’s hot pink and orange print. Then there's that vintage 'mid-60s black bra that shows the natural shape of the breast – without the ‘50s underwire or uplift – and lace panties that Bryant added a lining to “for modesty.”

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For anyone who wants to rewatch the final episode of Season 4, they will see Megan wearing a coral-colored dress. Bryant dressed her in coral for the first scene in Season 5: a 2-piece coral shift with a matching chevron striped coat. “The last episode in Season 4, she wore that color and I wanted to have that follow through for the first episode of this new season. Coral is a color that I use on her a lot. To me, it speaks to the romance of Don and Megan’s love story.

Bryant won’t spill any style secrets about what Megan will -- or won't -- wear in upcoming seasons. "You'll have to wait and see," she says.