Huyen Nguyen, Rebecca Rusch, and crew members study the map along the Ho Chi Minh Trail for the feature film project 'Blood Road' in Vietnam, Laos, and Cambodia in March, 2015. // Josh Letchworth/Red Bull Content Pool // AP-1UD72NRX51W11 // Usage for editorial use only // Please go to www.redbullcontentpool.com for further information. //