Watch Online HD on HDtoday. Beneath the spectacular beauty of Yellowstone National Park lies a ticking time bomb...a supervolcano that's overdue for its next eruption. When that day inevitably comes, it will trigger the end of civilization as we know it. See how recent earthquake swarms and other signals of activity have put scientists on high alert for a large-scale super volcanic eruption. Then, witness the worldwide effects of this cataclysmic eruption, which experts predict will produce energy equivalent to the detonation of 1,000 nuclear bombs.