Straight Up Films has launched development of a movie based on Donnie Eichar’s “Dead Mountain: The Untold True Story of the Dyatlov Pass Incident” about nine mysterious deaths in 1959.

Producers are Kate Cohen, Marisa Polvino and Casey Carroll of Straight Up Films with Eichar while Peter Sussman exec produces. Cohen and Polvino are producers on Johnny Depp’s sci-fi drama “Transcendence” and Natalie Portman’s Western drama “Jane Got a Gun.”

Brandon Lee Tenney has been hired to adapt “Dead Mountain,” centered on Eichar’s five-year probe into the unsolved 1959 deaths of nine experienced hikers in Russia’s Ural Mountains on an elevation known as Dead Mountain. Soviet investigators had found that the hikers had torn open their tents and run barefoot out into the snow on a night in February, stating that an “unknown compelling force” had caused the deaths.

Access to the region was subsequently blocked for hikers and adventurers for three years after the incident, which has been called Dyatlov Pass after the group’s leader, Igor Dyatlov.

The incident has sparked decades of speculation due to the unexplained causes of death, a final photograph taken by one of the hikers, signs of radioactivity and the lack of disclosure from the Soviet government of the era. Theories about the actual cause have included a failed Soviet military experiment and an attack by extraterrestrials.

Eichar’s book, a New York Times bestseller, includes access to the hikers’ own journals and photographs, government case files, dozens of interviews and the author’s retracing of the hikers’ fateful journey in the Russian winter.

Finnish director Renny Harlin directed a 2013 movie, using found footage as a story technique, about the incident. The film was titled “Devil’s Pass” and released by IFC in the U.S.

Tenney is represented by WME, Art/Work Entertainment and attorney Neil Meyer. Eichar is repped by WME and SussManagement.