'Mad Men' Don Draper's Plaid Sportcoat Causes a Fashion Freak Out (Video, Poll)

Michael Yarish/AMC

The dapper ad man, whose dark tailored suits inspired a modern menswear trend, broke out with a casual plaid sportcoat in last night's episode.

Mad Men fans were shocked last night when Jon Hamm's dapper ad man Don Draper -- known for his unchanging, elegant Cary Grant-style wardrobe -- donned a wild plaid sportcoat for an at-home party with his co-workers and their wives.

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First he didn't want to go to the dinner party, but his hot young new wife Jessica Pare's Megan Draper -- the show's latest fashion plate -- refused to take no for an answer. Then she sweet-talked him into wearing a new sportcoat she'd purchased for him. And when we see Don wear it, it almost looks like he traded in his Madison Avenue gig and got a job as a used car salesman.

In its day, the plaid sportjacket was cutting-edge fashion for men as they began to break out of conventional '50s suits and ties. Worn with a variety of sartorial accoutrements including colorful prints and patterns, flared pants, Nehru jackets, turtlenecks, the wardrobe change was complemented by longer hairstyles, facial hair and other signs that the times were a-changin'.

In a THR chat with Janie Bryant a year ago, the costume designer told us that the show's creator Matt Weiner saw Don Draper's style as being static and unchangeable -- and she didn't foresee any Nehru suits in his Season Five '60's wardrobe. 

But clearly, they had not planned on the powerful influence of a beautiful, fashion-conscious young wife. Bryant says she found the fabric, showed it to Matt and it inspired him to write an episode in which Megan buys him a sportjacket that he ends up wearing to the Campbells' dinner party.

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''It's definitely out of his usual (style). It's a louder palette, younger and fresher," says Bryant. "You can see bits and pieces of her influence in his life."

What the new Megan-inspired styles on the show will do to the current conservative Mad Men clothing collections currently in stores (Banana Republic, for example) is still unknown. But it's distinctly possible that these hipper late '60s looks will also return to the modern menswear market. To everything, there is a season. And with fashion, there are usually several through the decades.