One man died and another was badly injured after the Zorb they were strapped into got away from handlers at the Dombai ski resort in Abkhazia, and rolled into a gorge.
According to Russian state media, Denis Burakov, 27, and Vladimir Shcherbov, 33, were inside the sphere when it suddenly veered off course and ended up nearly a mile away beside a frozen lake.
Their harrowing ordeal was caught on at least two cameras, and an amalgam of both was uploaded to the Internet on Sunday. The footage shows two men attempting to prevent the Zorb from heading down the mountain slope, to no avail.
Toward the end of the video, a man can be heard saying "it's OK, it'll stop by itself."
Burakov sustained a broken neck in the fall and died on the way to the hospital. Shcherbov suffered multiple lacerations and a concussion, but is expected to survive.
RIA Novosti reports that an investigation into criminal negligence by the Zorb operators has been launched.
If convicted, they would face as much as ten years behind bars.