As a medic, Booth knew what his life would be like without a limb, and he wasn't afraid. He had seen fellow service members adapt relatively quickly to using a prosthetic. He figured he could return quickly to an active lifestyle, doing the things he enjoyed, like riding motorcycles.
Booth learned his tenacity from his dad, a Black Hawk pilot in the Gulf War who taught his son to remember when faced with a challenge: "It could be worse. Just get through it and get on with it."
On Nov. 29, 2011, doctors amputated Booth's lower right leg. He was fitted with his prosthesis, and began therapy three times a week to learn how to walk again.
But Booth soon noticed his injuries went beyond the physical. During the day, he felt on edge. At night, he had nightmares or insomnia. He started seeing a psychiatrist, who diagnosed him with PTSD and prescribed medication.
He wondered what he would do with his life when some Navy instructors who were training young medics invited him to the film studio.
A year ago in April, Booth started work with Strategic Operations. He has now performed with the group a dozen times, and he isn't bothered by the gore and gunfire. Rather, said Booth, the exercises have helped him deal with his post-traumatic stress.
"When we're at the point where the explosions and the gunfire is going off, I'm in a whole different mindset. I'm yelling and screaming and waiting for the corpsmen to come help me. So I'm not really worried about that (PTSD) anymore," said Booth, who has since stopped taking his PTSD medication. "It's more so about the guys coming to get me and really helping them."
Mental health professionals said they are not surprised Booth has found solace in his role-playing.
"For many of these guys it doesn't get better than that — to be able to know you are making a difference in the lives of people who are still in combat," said Nancy Commisso, a therapist with Easter Seals. "None of these guys want to be the patient — especially corpsmen who tend to be the ultimate persona of strength and someone who wants to help."
Commisso has had veterans with PTSD re-enact their combat experiences to diffuse the emotions burdening them.
"If they can go through that and come out of it OK, then they know, 'Whew!'" she said. "Then each time they do that, it can get better and better."
Lavell said having Booth has greatly enhanced the training because he bases his role-playing on his real-life experience, and is able to share tips that only a combat veteran can offer.
Earlier this year, Strategic Operations accepted its second veteran into the group: Redmond Ramos, another amputee corpsman whom Booth met while they were both recovering at the hospital.
On a chilly but sunny morning at the studio last month, shrill sirens pierced the air as smoke wafted from a crashed helicopter. A bloodied mannequin with no legs dangled from a strap off the rotor.
Booth sat under the prop, leaning against the aircraft. He jiggled his amputated leg to make it look like it was quivering. Marines scrambled to him, dodging Hollywood-style gunfire as Booth shouted: "Help me!"
One of the trainees fumbled as he hurried to put on a tourniquet and bandage.
Then he hoisted a limp Booth over his shoulder and ran as explosions boomed.
It was one of the numerous times that day Booth would be rescued.
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