Rachel McAdams Dating Ex of Kate Beckinsale (and Liz Lemon)

Wonderwall, Tuesday, October 5, 2010, 12:08pm (PDT)

By Kat Giantis

For all of you out there holding out hope that Rachel McAdams would soon jump back into the arms of onetime squeeze Ryan Gosling, grab some Kleenex and hide your "Notebook" DVDs, because she's seeing someone new.

Over the weekend, the prepossessing actress, 31, stepped out in her hometown of Toronto with Michael Sheen, 41, best known for his critically acclaimed performances in "Frost/Nixon" (as David Frost), "The Queen" (as Tony Blair) and "30 Rock" (as Liz Lemon's Bizarro Mr. Right, the persnickety Wesley Snipes).

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Paparazzi snapped the pair, who co-star in Woody Allen's upcoming "Midnight in Paris," smiling as they strolled hand-in-hand near McAdams' house.

Canada's National Post reports they were also spied looking affectionate while grabbing brunch and hitting an arts fest, where they popped in on a sing-along set to tunes from the movies.

Romance rumors first began at the Toronto International Film Festival last month, when LaineyGossip caught Rachel and Michael cozying up at a party for his forthcoming gut-punch of a drama, "Beautiful Boy."

"It's been going on over a month," a source told Us Weekly at the time. "It may turn serious!"

Sheen certainly knows something about turning serious. He has an 11-year-old daughter with former flame Kate Beckinsale, whom he split with in early 2003 after nearly a decade together.

The breakup happened soon after they co-starred in "Underworld." Beckinsale fell for the flick's director, Len Wiseman, and they married in May 2004.

On the surface, Sheen might seem an odd match for McAdams, who dated Josh Lucas after her fickle romance with Gosling petered out (more recently, she was linked to Owen Wilson and Jake Gyllenhaal, although the rumors were denied all around).

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But appearances can be deceiving. Seems the non-threatening-looking actor once clocked Jeremy Northam after he made the mistake of verbally abusing Beckinsale on the set of the 2000 flick "The Golden Bowl."

Explained Sheen, "It was because I thought he was being disrespectful to someone I loved."

The actor has been open about his admiration for McAdams, enthusing to "Entertainment Tonight Canada" last month about working with her on "Midnight in Paris."

"All my scenes were with Rachel," he said of shooting in the City of Light. "She's a genuinely lovely lady as well as being stunningly beautiful and very talented so, you know, she's got it all going on there."

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