It was undoubtedly the most ingenious and brilliant act of self-liberation in contemporary history, rivaling anything undertaken by Henri Charrière or Harry Houdini and making any fictional prison escape accounts look broadly drawn and crude by comparison. It was an undertaking of humanistic triumph so astonishing that it might have risked denial in later years were it not for the wealth of overwhelming evidence and the testimonies of survivors. In the early '40s, over 600 members of the Nazi prison camp Stalag Luft III set about digging three carefully-concealed tunnels, over three stories underground and several miles long, nicknamed "Tom," "Dick," and "Harry" -- escape routes sophisticated enough to even incorporate railways and electric lights. On the evening of March 24, 1944, the inmates planned to spring two hundred men in this way. Only 77 entered one of the tunnels -- many of whom were recaptured and killed -- but a few emerged from their incarceration unscathed. Over 60 years later, historians have devoted a wealth of literature to this miraculous occurrence, and Hollywood cinematized the subterfuge in 1963 with The Great Escape, but in this astonishing 60-minute video, WGBH's NOVA series digs into an area that has eluded researchers for decades -- locating the third tunnel -- "Harry" -- which eluded the Nazis by virtue of its careful concealment. In NOVA: The Great Escape -- The Most Daring Allied Prison Escape of World War II, viewers can journey back to the site of Stalag Luft III with NOVA's camera crew and a team of archaeologists to uncover and tour this long-lost relic and listen to the miraculous accounts of surviving prisoners and escapees.