Garrett Hedlund knows how to create a stink on a movie set, but not in the way you'd think. Just ask Leighton Meester.

In the movie 'Country Strong,' the characters played by Garrett and Leighton fall in love.

"Garrett is really awesome. I think he's wonderful; he's like a knight in shining armor in the movie and he also has this real vulnerable sweet side that comes out," the brunette beauty tells The Boot. "He's kind of a big kid."

However, there's one side of his personality that she admits can be a little "frustrating," although funny. One day, Leighton was getting her hair and makeup touched up during a lunch break. "[Garrett] put a stink bomb in the [make-up] trailer. It was just me and the hairstylist, and I'm going, 'Did he just...?' I'm sure the hairstylist is looking at me like, 'Did she just ...?' And then suddenly it gets to be too much to contain and I just have to run out screaming, and [Garrett's] just standing there laughing at me."

As moviegoers will see, Leighton clearly spent a fair amount of time in the make-up trailer, given her character's painted-on Barbie style. "I think it's really helpful to look like a totally different person to get into that headspace," she says. "I'd be touching my hair and I'd be like, 'Can I just wash it, please?' It was like this lacquered top and then underneath I kept on saying it felt like a cemetery with weeds and crazy stuff happening in there, [plus] eye lashes and lips, acrylic nails, the dresses and the little cross. But, yeah, that was a totally helpful part of the process."

Leighton plays beauty queen-turned-country starlet Chiles Stanton in 'Country Strong,' which hits theaters nationwide today (January 7). Watch her duet with Garrett in an exclusive sneak peek of the film below.

More on 'Country Strong':

'Country Strong' Movie Times

Gwyneth Paltrow Interview

Tim McGraw Interview

Garrett Hedlund Interview

'Country Strong' Characters Revealed

'Country Strong' Soundtrack Details