Top 10 Secrets and Mysteries

Individuals whose identities remain a mystery including D.B. Cooper, Jack the Ripper and the Man in the Iron Mask.

Visiting locations around the world with special religious significance from a Catalonian monastery to South Dakota's Black Hills.

Cryptic artwork including a crucifixion statue with real teeth, "Girl with a Pearl Earrings" and Leonardo da Vinci's "Last Supper."

Time-honored but not always scientifically accepted, non-traditional healing methods including herbal remedies and regression therapy.

A deep dive into the vanishings of people who were never found from a British secret agent to an intrepid explorer from a famous family.

World War II left behind a number of unexplained events, such as the identity of Anne Frank's betrayer and the ultimate fate of Raoul Wallenberg.

Associated with ancient Egypt, the practice of mummification occurred in other parts of the world, leaving behind some unanswered questions.

Never-solved urban mysteries include a walrus skeleton found in a mass London grave, Moscow's secret Metro line and Prague's occult origins.

Inexplicable conditions and illnesses include cases of mass hysteria and rare syndromes like Stendahl and Munchausen.

A look at classified military projects from false flag operations to America's recruitment of Nazi scientists after World War II.

Inventions that failed or were saying by the powers that be include Nikola Tesla's Wardenclyffe Tower and Stanley Meyer's water-powered fuel cell.

Examining global examples of human services fueled by religious and cultural beliefs that include ritualistic burnings and bloodlettings.

Ten notable cases of information that were deemed unacceptable for public consumption include missing Biblical gospels and a baffling manuscript.