History's Greatest Mysteries

With over 7,500 hours 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 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.

Booth family members share family lore, and what they believe is evidence of the assassin's escape, passed down through generations.

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 among the possessions of Maj. Jesse Marcel undergoes a crucial test.

Investigator Ben Smith travels to Jesse Marcel's hometown on Louisiana's Gulf Coast to speak with family members who reveal information that supports Marcel's story of a government cover-up.