“Mad Men’s” Vincent Kartheiser and the AMC show’s Season 5 guest star, Alexis Bledel, are getting married.

Alexis and Vincent are engaged, a rep for the actress confirmed to AccessHollywood.com.

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The former “Gilmore Girls” starlet, 31, played the mistress of Kartheiser’s ad exec character, Pete Campbell, for a three-episode arc on the popular AMC series last season.

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The stars first began dating in early 2012.

On the show, Vincent’s Pete fell hard for Alexis’ Beth, despite both of them being married. The romance appeared to end for good though, on “Mad Men,” when Beth had a lobotomy.

It’s not the first time Alexis has been romantically linked to a co-star — she dated her “Gilmore Girls” on-screen boyfriend Milo Ventimiglia for several years.

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An impending walk down the aisle isn’t the only news for Alexis – she’s also lined up a new TV gig.

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Alexis will co-star in a new FOX sitcom pilot called “Friends & Family,” alongside Jason Ritter per EW. The show is based on the UK series “Gavin & Stacey.” Alexis will play Stacey to Jason’s Gavin.

— Eric Anderson

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