The movie based on the Granite Mountain Hotshots will hit theaters next month.

A trailer released Friday for Only the Brave describes the director's mission of authenticity while depicting the 19 Arizona firefighters who lost their lives fighting the Yarnell Hill Fire in 2013.

"Our homes, our ways of life are all protected by guys going out there and marching into fires 100,000 miles wide with an ax and shovel," a voice says in the trailer.

"It's a tribute to them, and it's a story of real heroes, actual flesh and blood, who do these extraordinary things," actress Jennifer Connelly says in the trailer.

Only the Brave hits theaters Oct. 20. It's directed by Joseph Kosinski and stars Josh Brolin, Miles Teller and Jeff Bridges. The movie was rated PG-13. The movie was filmed in New Mexico.

Kosinski also directed "Tron: Legacy" and "Oblivion."

PHOTOS: Granite Mountain Hotshots Memorial State Park dedicated