“They’ve always had a spark, and when the opportunity presented itself, they took advantage of it,” snitched a source close to both stars.
The acting stud, 47, and willowy blonde, 40, have been quietly meeting up in the Los Angeles suburb of Los Feliz where they both live, added the source.
Jon’s 18-year relationship with actress Jennifer Westfeldt ended in 2015, around the same time “Mad Men” folded — and sources believe that’s when he started seeing his on-screen wife!
“There was never any doubt that they would stay in touch after the show ended,” the source spilled. “When Jon’s relationship with Jennifer came to an end, the door opened for him and January to become more than friends.”
After Jon’s guest gig on “The Last Man on Earth” with cast regular January in 2016, they took things to the next level, according to the insider.
For now, the Tinseltown twosome — he played cheating ad man Don Draper to January’s chain-smoking Betty on “Mad Men” — are keeping things on the down-low.
“A lot of people would love to see them go public as a real couple, but they’re happy with the way things are,” the source spilled.
“They want to keep things quiet and casual. But their chemistry is undeniable!”
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