Turns out, appearing in a film alongside Emily Blunt isn't exactly easy. We'll discuss the struggle it took for a certain co-star to match her look.

However, although it might be hard to believe, Emily faced her own struggles at a young age, having difficulty with a stutter at a younger age. Her education played a big role in eventually losing it. Even she wouldn't have anticipated breaking into the world of Hollywood back then.

Once she landed an agent, her career changed and her real breakout party took place in 'The Devil Wears Prada'. From then on, the roles started to fall in.

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Back in 2012, she appeared in the comedy-drama, 'The Five-year Engagement'. The cast featured lots of stars, though it wasn't a huge hit at the box office, bringing in $53 million, of a pricey budget of $30 million. Nonetheless, Blunt had a great time with the role, though her co-star might be thinking otherwise.

We'll reveal which actor was forced into losing lots of weight for the role, in order to keep up with his co-star. As it turns out, it wasn't the first time he was asked to transform for a role...

He Had To Put On Weight In The Past

The actor in question is none other than Jason Segel!

He's used to transforming, though, in the past, the opposite held true as he was told to gain weight. At one point, Segel was eating 12-pizza pockets a day in order to look the part for his film, 'The End of the Tour'.

"The first week is fun, and after that, every day feels like Thanksgiving night, like, you’re just done. You have no energy or anything like that.”

“By the end, I was running out of time. I had about two weeks left so I put myself on a Hot Pocket diet, which was two Hot Pockets every three hours,” he said.

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“It was horrible. I was eating like 12 Hot Pockets a day at that point. I was so sick of them and I swore I would never eat another Hot Pocket.”

Not the easiest transformation, though he was forced into a different type of scenario alongside Emily Blunt, one that actually improved his health.

He Was Told To Lose Weight By The Studio For 'Five-Year Engagement

As if appearing alongside Emily Blunt isn't stressful enough, the veteran actor was told he needed to drop 35-pounds for the role. Some might find it harsh, given that it wasn't a physical role and in truth, the transformation was only needed so that Segel can match her, at least somewhat, in terms of looks.

"I was told that it had to be conceivable that Emily Blunt would ever choose me to be her husband,” the 32-year-old recalled, adding, "which is fair."

Along with the healthy eating, Segel got a trainer and worked out twice a day, which actually helped his health a great deal.

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However, he still got away with eating a few extra calories on the set, thanks to his smarts, "What they didn't anticipate is that I'm very clever. I play a chef in the movie, so there are a lot of scenes where I had to eat, so I would pay my co-stars nominal amounts of money to mess up their lines during the scenes so I would get to keep eating."

Despite the transformation, Segel had a great time with the film.

Segel Still Had A Great Time With The Film

At the very least, despite the demand, Segel enjoyed the film, especially the improv part of it.

"We do a lot of improv. This is the first movie that Nick and I have shot on digital so we had the opportunity to let the camera roll much more freely without worrying about film costs. I think the DNA and the intent of the scenes stay the same but there’s nothing like having people speak in their own voice. You can just feel it on screen."

In addition, his chemistry alongside Blunt was almost effortless, given how close they are off-camera.

"A movie about a couple that’s known each other for a while, it should feel like they’ve known each other a while. One of my giant pet peeves are movies where it just looks like they’ve chosen two model Hollywood actors that had successful movies the year before and now they’re just clumped together."

"You can feel it. And this movie, even the in-between scenes are the ones I’m most proud of, the scenes where we’re just walking together. Because it looks like we know each other."

"It looks like best friends. So I knew that I wanted to write it for her going in and she agreed."

Despite the initial struggle, it turned out to be a great experience for Segel.

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