For twenty years a lethal secret has been hidden in the Himalayas above Katmandu. A U.S. biological experiment – using military criminals – went horribly wrong, and the escaped subjects have survived. An elite military unit is sent to wipe them out. As two American mountaineers race to save a woman climber from a catacomb of death, they uncover the real terror that is behind Operation Snowman – and the only way out is through the use of skills they learned in combat.