Emily Blunt plays a bride-to-be with a long and bumpy build-up to her big day, in new comedy The Five-Year Engagement.

When it came to her own nuptials everything went far more smoothly – even with a guest list that resembled a Hollywood awards ceremony.

Emily married actor John Krasinski, one of the stars of the US version of The Office, in an intimate ceremony in Lake Como, Italy in 2010, with George Clooney, Matt Damon and Meryl Streep, her co-star in The Devil Wears Prada, looking on.

The reason it was so relaxed was, Emily says, because she didn’t reveal any Bridezilla tendencies.

“I wanted to keep it really laid-back. I’m quite decisive, not one of those people who says, ‘Oh, what about this, what about that?’ I’m just like, ‘That’ll do, that’ll do, that’ll do’, because I just think it’s the day that’s special, not all of the stuff that comes with it.

“The day should be kind of freewheeling a little, because something could go wrong. You’ve just got to roll with the punches.”

Her other half in The Five-Year Engagement is close pal Jason Segel, who co-scripted the film and wrote the role of British academic Violet with Emily in mind.

The story begins with talented chef Tom (Segel) popping the question. The wedding gets postponed though, and cracks emerge after Violet lands a new post in Michigan and Tom quits his job to go with her.

As the big day gets further delayed, the couple begin to wonder whether they are really meant to be together.

Despite the grace and poise which helped secure roles such as Queen Victoria in The Young Victoria, and ballerina Elise Sellas in thriller The Adjustment Bureau, 29-year-old Emily is clearly game for a laugh, demonstrating her gift for slapstick as Violet gets shot in the leg with an arrow, runs into an open car door and performs an impeccable impression of The Muppets’ Cookie Monster during a row.

“We didn’t really want to do that Hollywood gloss of the romantic comedy that we’re used to seeing,” she says. “We wanted to make it really real and accessible and naturalistic, kind of messy.”

And the Cookie Monster impression?

“The director Nick Stoller’s daughter gets him to do silly voices at the most inopportune moments, like when he’s in a talk with his wife and she’s like, ‘Do the silly man voice’.

“So I think that’s where the idea came from, and I love how funny it is to see two people arguing as Cookie Monster and Elmo. It undercuts the emotion and earnestness of the scene.”

Since her big break playing the ice-cold office bitch in The Devil Wears Prada, Emily has taken on a wide variety of roles, from Ewan McGregor’s love interest in Salmon Fishing In The Yemen, to voicing a garden gnome in animated movie Gnomeo & Juliet. Upcoming films include the sci-fi war flick All You Need Is Kill alongside Tom Cruise, and futuristic thriller Looper, with Bruce Willis.

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.”