Meet the new faces of climbing: 15-year-old Ashima Shiraishi and 16-year-old Kai Lightner are the leaders of a new generation taking the sport to the next level. Ashima, a New York City native, is the youngest person and the first female to climb 5.15a. Kai, from Fayetteville, North Carolina, became a national climbing champion as a high school sophomore. Young Guns follows these two friends and prodigies as they spend their summer vacation in Norway, where the legendary Flatanger cave forces them outside their comfort zone. In the finale, Ashima travels on to Japan to set a new standard on Horizons, a fierce 30-move boulder problem at the cutting edge grade of V15.