In some ways, Rachel McAdams is a classical movie star. She can play romantic leads like nobody’s business in hits such as “The Notebook” and “The Time Traveler’s Wife.”

She can also switch from serious to comedy, as in “Wedding Crashers” and last year’s “Midnight in Paris.”

But she’s also a modern movie tough girl, backstabbing in “Mean Girls,” thwarting terrorists in “Red Eye” and kicking behinds in “Sherlock Holmes.”

In “The Vow,” a romantic drama loosely based on a true story, she plays Paige, a sculptor happily married to a recording studio owner (Channing Tatum), who loses her memory of him after a car accident.

But she does recall her parents (Sam Neill and Jessica Lange) and a former boyfriend (Scott Speedman) whom she had previously jettisoned from her life.

At a recent Hollywood publicity event for the film, McAdams called real-life couple Kim and Krickitt Carpenter, the inspiration for the movie, “more amazing” than the fictional characters because they stayed together.

For the movie, though, director and co-writer Michael Sucsy (“Grey Gardens”) has altered the story: Paige pulls away from her spouse and he tries to win her back.

“The more you remind someone of something they don’t remember, the more you push them away,” said McAdams. “The very act of trying to get someone back makes the chasm between them even greater.”

Sucsy said McAdams’ worries about her chemistry with Tatum were unwarranted: “In this movie, if you have chemistry, it’ll work, and if you don’t have chemistry, it’ll actually still work, because of the nature of this film. But the fact that they have it and are pretending to not have it, creates a much better tension.”

Of course, most women in the audience would agree that waking up to Tatum leaves little room for doubt.

McAdams joked, “I always wanted to do a take where I say, ‘YOU’RE my husband? OK!’ But then we wouldn’t have anywhere to go.”