A leggy starlet with a headful of hair-sprayed curls emerges from her convertible to welcome a grizzled, yet handsome man after his long flight.

The message to “Mad Men” viewers watching the AMC show’s season opener is clear: It sure didn’t take long for Megan Draper to adjust to life in the City of Angels.

What helped make the scene so memorable was the ice blue, itsy bitsy, teeny weeny babydoll dress worn by actress Jessica Pare.

Aside from causing fashionista fan girls to swoon across the Twittersphere, the episode also garnered costume designer Janie Bryant and her team an Emmy nod — Bryant’s fourth for the series and a category she won (with Le Dawson) in 2005 for “Deadwood.”

“We wanted to give Megan an amazing dramatic entrance,” Bryant says. “That was actually a vintage dress that I used. I loved it because it was the color of the sky, it also had the chiffon sleeves and the bow. I love the whole movement of that costume.”

Like “Mad Men” creator Matt Weiner, Bryant is notorious for her attention to detail. “We also made all the airline uniforms so that they were specific to the periods,” she says. “It was a matter of research to find out what the flight attendants’ costumes looked like.”

The fans pay just as slavish attention to the clothes: Bryant unintentionally fueled fan speculation that Megan was a stand-in for doomed actress Sharon Tate when she dressed her in a white T-shirt with a red star, similar to one Tate wore in an Esquire photo shoot. But Bryant ultimately said it was just about Megan making a political statement — not a hint about the character’s fate.

During the show’s early seasons, the costume department would famously sew characters’ undergarments so that they accurately reflected the silhouettes from the form-fitting early ’60s. Though the show has progressed to the late ’60s, not all the characters have burned their bras.

“Some of the characters remain with their classic design, and some move on,” she says, citing Megan and Sally Draper (Kiernan Shipka) and Rich Sommer’s Harry Crane as those who are a bit more fashion-forward.

As “Mad Men” prepares to air its final season next year, Bryant says she is focusing on selling “Janie Bryant’s Hollywood,” the reality competition show she’s developing with “Fashion Star’s” E.J. Johnston and James Deutch.

Will she ever be done with period projects?

“Never,” she says laughing. “It’s my favorite.”