Lucca was already the most accomplished military working dog in history when on her last deployment she stepped on an improved explosive device in Afghanistan.

"We go out in the mornings, try to beat sunlight, to get to the objective early," explained her handler, Marine Corporal Juan Rodriguez, in the new Fox Nation series "Hero Dogs," hosted by "Fox News @ Night" anchor Shannon Bream.

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"About four hours into the patrol, while looking for an IED she found one," he said, then Lucca went to work searching for more.

In Iraq and Afghanistan, military working dogs are used to sniff out stockpiles of insurgents' weapons caches and explosives hidden in the terrain. It is dangerous and sometimes deadly work.

Marine Master Sergeant Chris Willingham, Lucca's first handler, told Bream about the tragic deaths of another dog and handler team in Iraq in 2007.

"[Army Cpl. Kory D. Wiens] and [military working dog] Cooper went out on patrol and they went to search a compound, and as they were making an approach, a large IED went off," said Willingham in the Fox Nation show.

"Cooper, Kory, and seven others were killed," narrated Bream. "Less than three months earlier, Kory had welcomed Chris and Lucca to Iraq."

After hundreds of missions together, during which Lucca proved herself again and again, Willingham was reassigned to a unit that protects America's embassies around the world.

Lucca was sent to Afghanistan.

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"Chris was allowed to pick Lucca's next partner," said Bream. "He knew [that] Juan Rodriguez, a corporal and fellow dog trainer from Chris' 2010 deployment, was the only choice."

"This was going to be her last deployment," said Willingham, "because she'd be about 8 years old at that point and she'd be too old to stick around to get ready for another deployment."

In 2012, a short time after Willingham arrived at his new assignment in Finland, he received an email — there had been an incident and it did not look good for Lucca.

While searching a compound, Lucca identified an IED and then began to search for more. As she moved, she stepped on a buried device and it exploded, badly injuring her leg.

Rodriguez scrambled to save her, trying a tourniquet around her leg and carrying her back to safety. From there, Lucca was evacuated by helicopter and rushed into surgery.

"She was treated like any Marine. She got medevac, got called in as a Marine — just special instructions that she was a dog," said Rodriguez. "I was always with her, never left her side."

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After hours of consultation, a Marine doctor determined that it was best to remove Lucca's entire left leg.

"Her recovery was almost as heroic as her battlefield exploits," narrated Bream.

"Lucca was walking in 10 days," remembered Willingham. "She didn't have any permanent ear and eye damage. She didn't have any internal shrapnel to deal with and most importantly, she had the same personality and same spirit that she had before the blast, which is pretty amazing."

To watch all of the new series, "Hero Dogs," and hear more about Lucca's life after the military including her emotional reunion with Willingham, go to Fox Nation and sign up today.

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