Left with no other option, John plans to drill across the mountain to get underneath the waterfall, but the weather won't make this an easy task. Meanwhile, Rick finds an artifact at Breach 6 that could confirm Japanese military presence on the mountain during World War II. Then, Levi and Geo make a grim discovery in the tunnel that risks shutting down the site indefinitely. And finally, Bingo meets someone with rare and valuable knowledge on the whereabouts of Yamashita's gold.