Jessica Paré hasn't been on Mad Men from the beginning, but she is quickly becoming its hottest star. Viewers were skeptical of Don Draper's (Jon Hamm) young wife until her breakout performance of "Zou Bisou Bisou" at her husband's birthday party last season. Since then, she's gone from secretary-cum-trophy wife to complex character.

Paré, who is French Canadian like her character, covers the March issues of ELLE Canada and ELLE Québec. She expected to be a one-episode guest star, like most of Don's conquests, but fortunately for her (and us), that didn't happen.

"The first time Megan and Don kissed, the costumer turned to me and was like, ‘Well, it was great working with you, buddy.' And then it turned into being Mrs. Draper, which I still can't fucking believe. I'm so grateful," she said. Paré also knew "Zou Bisou Bisou" was infectious before it became an iTunes hit.

"I knew the song was catchy when I started working on that episode and everybody in the production office was singing it incessantly, and then I was singing it for about six weeks and then everybody in the cast was singing it for the next two," she admitted. "Hats off to Matt Weiner for choosing something that would capture people's imaginations in such a great way."

Yeah, it was Matt Weiner. Mad Men returns for its penultimate season April 7!

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[via ELLE Canada]