Millions of people around the world live in the shadow of active volcanoes. Under constant threat of massive volcanic eruptions, their homes and their lives are daily at risk from these sleeping giants. From Japan's Mount Fuji to the "Sleeping Giant" submerged beneath Naples to the Yellowstone "Supervolcano" in the United States, NOVA travels with scientists from around the world who are at work on these sites, attempting to discover how likely these volcanoes are to erupt, when it might happen, and exactly how deadly they could prove to be.

Encoded with permission for digital streaming by Infobase on December 08, 2013. Learn360 is distributed by Infobase for Films for the Humanities & Sciences, Cambridge Educational, Meridian Education, and Shopware.

Introduction: Deadliest Volcanoes (2:04) -- Sponsors: NOVA (0:40) -- What Causes an Eruption? (3:14) -- Eruption of Iceland's Eyjafjallajokull (5:53) -- Ring of Fire (3:05) -- Yellowstone's Unusual Location (4:02) -- Future of Yellowstone (1:59) -- Italy's Vesuvius (1:30) -- Determining Volcano's "Throat" Size (5:52) -- Italy's Campi Flegrei (4:52) -- Campi Flegrei: Drilling Project (2:35) -- Italy's Daily Erupting Stromboli (6:14) -- Ancient Lahars of Mt. Rainier (4:01) -- Studying Mt. Rainier's Streams (3:07) -- Orting's Lahar Warning system (3:02) -- Sponsorship & Credits: Deadliest Volcanoes (1:17).