Third time may be a charm for professional ski mountaineer and high-altitude ultra-runner Kilian Jornet. Jornet intended to climb Everest in 2015 when the earthquake shut down the mountain. He tried again in 2016, from the North side in Tibet, but abandoned the attempt due to bad weather and snow so unstable that it prohibited his chosen climbing method — running all the way up and down in one push. Like last year, Jornet's attempt in May will certainly be the most unconventional of the season. He's again planning to start at Rombuk, on the base of the North side, and complete a non-stop ascent up and down with no oxygen, no fixed lines, and no support. He'll be accompanied by one other person, Seb Montaz, an extreme athlete and filmmaker from France.