Emily, the daughter of an English teacher and a QC, took up acting after “an amazing teacher” encouraged her to sign up for school plays to help her overcome a childhood stammer.

While she was at Hurtwood House, a sixth-form college known for its performing arts, she was spotted by an agent and made her professional debut in a musical at the Edinburgh Fringe while still studying for her A-levels.

In 2004, she had a breakout role in dark British drama My Summer Of Love – based on Birmingham writer Helen Cross’s acclaimed first novel – picking up an Evening Standard British Film Award for most promising newcomer with co-star Natalie Press.

Emily now live in Los Angeles with her husband, whom she describes as “the funniest man alive”.

In spite of the A-list wedding, everyday life for the couple sounds low-key.

“At the moment I get chunks of time off, which we spend together,” she says. “It’s also nice to have a shared understanding of what each other does.”

The down-to-earth actress – who ensures her US home is well stocked with Marmite – seems unlikely to ever succumb to Hollywood diva behaviour.

“I have great friends. And I think you’ll always remain grounded if you wash the dishes every day and buy your own toilet paper.”

Emily is keen to “keep mixing it up”, appearing in both blockbusters and indie films. As well as this week’s romcom with Jason, next week she will be seen in the low-budget comedy drama, Your Sister’s Sister.

She plays a woman who invites her grieving ex-boyfriend to recuperate in her family’s cabin, only for him to drunkenly get involved with her gay sister.

“I like the variety out there,” she says..

“I don’t think you can strategise the jobs that you do. You’ve just got to pick what you love.”