Is there something Rachel McAdams needs to tell Us?

The actress showed off a noticeably fuller figure -- and a giant baby bump! -- Wednesday in Notting Hill, London, but McAdams, who is currently dating Michael Sheen, isn't really expecting...other than on the big screen.

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Filming scenes for her latest flick, About Time, The Notebook alum McAdams, 33, appears in the lead role as Mary, a woman who comes into contact with actor Domhnall Gleeson's time traveler character, Tim, and sweeps him off his feet.

Love Actually director Richard Curtis is attached to helm the flick, and reportedly once courted New Girl's Zooey Deschanel for the lead role that later went to McAdams.

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Working long days on set in and around London has to no doubt be a challenge for McAdams, who met her boyfriend Sheen, 42, on the set of Woody Allen's 2011 Oscar-winning film Midnight in Paris.

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"Michael and I never spend more than three weeks apart -- we rack up a lot of air miles -- but you have to be quite adaptable in this business whether you are in a relationship or not," McAdams recently told The Sunday Telegraph's Stella. "Trying to establish roots somewhere is a bit of a joke."

About Time -- costarring Bill Nighy, Tom Hollander, Margot Robbie and others -- is expected to hit theaters next year.

This article originally appeared on See Rachel McAdams With a Baby Bump!