How a civilian engineer became a World War II spy -- twice -- and stopped the Duquesne spy ring that had infiltrated America's borders.Double-agent William Sebold talks with Captain Fritz Joubert Duquesne, German spy, who was unaware that FBI agents were taping the whole episode behind a two-way mirror.FBI/Library of Congress/Wikimedia Commons William Sebold never planned on becoming a spy, but fate had different plans. The German-born Sebold had fought for Germany in World War I, but had become an American naturalized citizen after living and working in America for years.

When Richard Lawrence tried to assassinate Andrew Jackson in 1835, he failed in spectacular fashion — then Jackson fought back.Andrew Jackson once declared: “I was born for the storm; calm does not suit me.” Throughout his life, Jackson was no stranger to close calls. The scrappy president from Tennessee had been a boy when the Revolutionary War broke out, and he cut his teeth fighting against the British. When he was captured in 1781, a British soldier slashed him for refusing to shine his boots, giving Jackson scars on his hand and face.

One of the worst serial killers in American history, John Wayne Gacy performed as "Pogo the Clown" by day and murdered young men and boys by night.On January 2, 1972, 16-year-old Timothy McCoy got up early to make his host breakfast. He had met John Wayne Gacy at the Chicago bus terminal the night before, and Gacy let him stay over while he made his way home to Iowa after spending Christmas in Michigan.

An infamous punishment used to maintain order at sea in the 17th and 18th centuries, keelhauling was when sailors would be dragged under ships as punishment.Ancient forms of torture are notorious for their cruelty and creative ways of inflicting excruciating pain. The practice of keelhauling is no exception. Said to be used by the navy and pirates in the 17th and 18th centuries, keelhauling is a form of punishment in which the victim is suspended by a rope from the mast of the ship, with a weight attached to his legs.

It is unknown why Susana Carrera was targeted and held for a $207,000 ransom. No arrests have been made in regards to her kidnappers.TwitterSusana Carrera The body of a decapitated Mexican businesswoman has been found in a bag a week after her disappearance with an unsettling note which read: “This happened to me because my husband played the tough guy and didn’t want to pay my ransom,” FOX News reported. Victim Susana Carrera’s body was found last Wednesday stuffed into a bag and left in a parking lot in Coatzacoalcos, Veracruz.