Marine fights to keep her military dog in 'Megan Leavey'

LOS ANGELES (KABC) -- The new film "Megan Leavey" is inspired by the true story of a young woman who joins the Marines.

The character makes that decision during a tough time in her life, and it's a decision that would end up changing her life forever.

Kate Mara plays the title role and literally "suiting up" in all that gear presented a unique set of challenges for the actress.

"I think I almost fell over," said Mara. "I thought, 'Oh my gosh, I'm going to be so strong by the end of this movie.' Yeah, it was a challenge."

Military life is far from easy, but Leavey discovers her purpose when she's assigned to clean up the K-9 unit.

She may have trouble bonding with people, but finds a connection with a military combat dog named Rex. Together, they would help save countless lives during their deployment in Iraq; but not without injury to either of them.

"We wanted that feeling of what it's like be searching and searching with your dog for the IED for days on end and what it means to find that IED," said director Gabriela Cowperthwaite: "That is the difference between hundreds of people being killed and people surviving."

Mara worked with three different dogs during the course of shooting the film.

"But one, named Varco, was the one that really was in almost every single shot with me," said Mara. "And I did become very attached to him."

Everyone involved with the film never forgot they were telling a real person's story.

"She's a force of nature, the real Megan Leavey," said Cowperthwaite. "She was there during part of boot camp. She's actually in the film."

"She's in the film screaming at me, telling me that I'm basically a loser," said Mara. "Can't do pullups. It's like a whole thing. It was great."

"She's amazing," said Cowperthwaite. "You just want to do her story justice."

"Megan Leavey" opens in theaters Friday and is rated PG-13.