At 5am in Olympic Valley, the dark breaks open. Headlamps flare, cowbells ring and 370 runners move towards the mountains. The Western States Endurance Run, widely known as WSER 100, is a 100.2-mile ultramarathon from Olympic Valley to Auburn, California. Ahead lie more than 18,000 feet of climbing and nearly 23,000 feet of descent before the finish at Placer High School. The route climbs straight into the Sierra high country, crosses the Granite Chief Wilderness and drops into the scorching canyons of the American River. Remote, exposed and relentless, conditions can swing from freezing winds to punishing heat. Even in the unusually cool conditions of 2026, the distance and accumulating damage were brutal. This documentary sports photography series follows British ultrarunner and Adidas TERREX athlete Fiona Pascall, together with the crew working to keep her race alive. For hours she is alone on the trail. Then each aid station erupts into noise and movement. Packs are pulled off and replaced. Bottles, food, ice and instructions pass rapidly between hands. Water hits skin and kit is packed with ice. The whole process is closer to a Formula 1 pit stop than a moment of rest. Fiona disappears back onto the trail, the crew pack the car and the chase begins again. Mile after mile, the pattern repeats as fatigue deepens and the margins narrow. The 2026 women’s race was unprecedented, with seven of the ten fastest women’s times in Western States history recorded that day. Despite finishing eighth, Fiona’s time of 16:32:05 would have won every previous edition apart from 2023 and 2024. A staggering achievement just five years into her ultrarunning career. The images move between control and chaos, exhaustion and forward motion, revealing the collective effort behind an intensely individual race.