On a blistering June morning in 2013, Arizona's Granite Mountain Hotshots elite firefighting squad went into the wilderness to protect the town of Yarnell from a ferocious blaze.

By the end of the day, all but one of the 20 man crew were dead.

It was the largest loss of life among American firefighters since the attacks of September 11, 2001 and the deadliest US wildfire in more than 20 years.

"Only the Brave," a major new movie starring Josh Brolin, Jennifer Connelly and Miles Teller, pieces together the final hours of the crew.

Its release on Friday next week could hardly be more timely, with the deadliest week of wildfires in California's history leaving 33 dead and hundreds still missing.

The movie offers insight for those watching the increasingly grim headlines from northern California into the lives of the men and women who run toward danger to protect people and property, real-life heroes in an age of superhero movies.

"We all are asked to be brave in our own lives, and bravery is such an interesting thing," seven-time Oscar nominee and one-time winner Jeff Bridges, who co-stars, told a news conference in Los Angeles.

The 67-year-old veteran of more than 70 movies wondered aloud if bravery of the type displayed by the Hotshots required them to feel fear, or if it was just instinctual.

"Or does bravery take practice... being at peace in this uncomfortable situation? That's something that all of us can look at in our own lives," he said.

The Yarnell Hill Fire was ignited by a lightning strike on June 28, 2013 and, two days later, the gusting winds fanning it changed direction, twisting and rotating its progress.

Sole survivor Brendan McDonough, who was the lookout for the Hotshots that day, alerted his crew and retreated down the mountain.

As the winds gusted ever harder and the fire rapidly picked up progress, supervisor Eric Marsh, a 20-year veteran, guided his crew from one protected "black zone" -- charred ground protected from the blaze -- toward a different safe site.

- Cut off -

But the flaming front approached faster than anyone had anticipated, and the crew's escape route was suddenly cut off.

Caught in a freak inferno, they deployed their fire shelters but perished in the extreme heat.

The story resonated particularly strongly with Brolin, who drew on his experience as a volunteer firefighter in Arizona when he was in his 20s to play Marsh.

The 49-year-old actor, Oscar-nominated for Gus Van Sant's "Milk," describes firefighters as the "last profession that are untouchably uncorrupt."

Hotshots, the country's top wildland firefighters, don't carry water, instead literally fighting fire with fire, using chainsaws to fell trees and burn barrels to light blazes to halt the progress of wildfires.

The term "hotshot" is usually reserved for Forest Service special units and the Granite Mountain crew were just a band of local firefighters that Marsh dreamed of turning into an elite crew.

This had never been achieved, but years of training paid off and they became the first certified municipal hotshot crew in the United States.

The 20 actors playing members of the unit immersed themselves in a boot camp led by real-life hotshots in the mountains outside Santa Fe, New Mexico.

Sleeping in the dirt under the stars, they ate military rations, hiked most of the day and learned how to become wildland firefighters.

Teller described the camp and 60-day shoot as a "kick in the gut," adding that the "collective suffering" helped the cast bond.

"I think I underestimated the physical aspect of the job. I knew it was going to be tough, but I wasn't versed on hotshot training before I showed up," said Teller, 30.

- Bravery -

"Only the Brave" features five fires portrayed through a mixture of actual blazes, special-effects fire and computer-generated imagery.

The crew built a two-acre forest set behind Santa Fe Studios, with more than 600 pine, juniper and spruce trees, bushes, grass, rocks and a drip irrigation system.

The fires were ignited from liquid propane tanks, with flames bursting 30 to 100 feet (nine to 30 meters) into the air.

"The actors will tell you, we had fire on set and it was hot," said director Joseph Kosinski, of "Tron: Legacy" and "Oblivion" fame.

"I was just remembering yesterday a scene that Josh was in where he was standing very close to some large flames and after the take I was like, 'Are you good, man? Are you okay?' He was like, 'Yeah, no problem.' And he turned around and the pack on his back had melted."

The Granite Mountain Hotshots crew was discontinued after the tragedy, with Arizona's Forestry Division finding no evidence of negligence.

But the Industrial Commission of Arizona, which oversees workplace safety, blamed the division for the deaths, arguing that officials knowingly put protection of property ahead of safety and should have pulled crews out earlier.

A memorial in the town of Prescott, where the firefighters were based, was attended by thousands, including representatives from over 100 hotshot crews and Vice President Joe Biden.

"All men are created equal and then some become firefighters," Biden said, paying tribute to the bravery of the Granite Mountain Hotshots.

Source: AFP