Whether it is the existence of aliens, the possibility of life after death, or sightings of strange creatures, the lure of the unknown has always been irresistible. Now, using the latest scientific techniques, this series seeks to ascertain whether these strange occurrences, myths and startling phenomena are merely illusions or actually real. Each episode highlights one topic, including: Bigfoot, one of America's most-sighted-but-never-seen beings; the Eastern State Penitentiary, one of America's most haunted locations; and a possible UFO Invasion on March 13, 1997 in Nevada and Arizona. (Source: National Geographic Channel)