History's Greatest Mysteries

Following news of the history-making discovery of Sir Ernest Shackleton's ship the Endurance, this is a look at his historic and ill-fated 1914 Antarctic expedition resulting in the loss of the highly revered ship.

Discover whether John Wilkes Booth evaded justice and lived for decades after killing Abraham Lincoln.

A dust-covered box hidden in a British manor house for 108 years contains the personal notes of Lord Mersey, the respected British jurist and politician charged with investigating the sinking of the Titanic in 1912.

With over 7,500 hours of investigating the mystery, top D.B. Cooper expert Eric Ulis believes that he's found the true location where Cooper landed during his daring dive.

A cryptic journal sparks an unprecedented investigation into whether a UFO crashed at Roswell, N.M., in 1947; Major Jesse Marcel's journal may contain coded clues to the truth behind Roswell.

A cryptic journal sparks an unprecedented investigation into whether a UFO crashed at Roswell, N.M., in 1947; Major Jesse Marcel's journal may contain coded clues to the truth behind Roswell.

A former CIA operative's investigation into the Roswell crash arrives at a critical moment when the mysterious journal found in the possessions of Major Jesse Marcel undergoes a crucial test.

The grandchildren of Major Jesse Marcel, the first person to investigate the mysterious 1947 Roswell crash, use his diary to discover the truth of what really happened.

This multi-part investigation examines the controversial Roswell UFO crash of July 1947. In this first part, cryptic portions of a journal kept by wreckage investigator, US Army Major Jesse Marcel, are evaluated for their authenticity.

Discover the controversial Roswell UFO crash of July 1947. In this second part, investigators attempt to determine the content of a memo held by Gen. Roger Ramey in the controversial "this is a weather balloon" newspaper photo.