1. Richard Colvin Cox. In January 1950, Cox was a second year cadet at West Point. That month, he met a man known as “George”. He met George three times over the course of a week. Cox had mentioned to his roommate that he didn’t like “George”, but he continued to accept phone calls from him. The third time they met, Cox and “George” vanished, never to be seen again.
2. Leo Burt. Burt was indicted for the August 24, 1970 bombing of Sterling Hall at the University of Wisconsin-Madison. The bomb killed one and injured several others and caused $2.1 million in damages. Burt fled to Canada and the police closed in on him but he slipped out of their grasp at the last second and has never been heard from since. However, tips still come in about possible sightings.
3. DB Cooper. On November 24, 1971 A man calling himself DB Cooper hijacked a Boeing 727 between Portland, Oregon and Seattle, Washington. He extorted $200,000 ($1.1 million in 2016 dollars) and then jumped out of the airplane and has never been seen since. Some of the cash was discovered but no other trace was found. Investigators can’t even agree on whether he knew what he was doing by jumping from the plane or was just a reckless amateur.
4. Suzy Lamplugh. On July 28, 1986 the friendly 25-year old real estate agent vanished. The only clue to her disappearance was an entry in her appointment book to meet Mr. Kipper at a house she was selling. He’s never been seen. Police tested over 800 bodies and skeletons of people who matched her appearance, but she has never been found.
5. Rebecca Coriam. Rebecca was a 24 year old employee on the Disney ship Disney Wonder. The ship was on the Pacific Ocean, off the coast of Mexico when security cameras recorded her taking a phone call. After that sighting, she seems to have vanished into thin air. Despite repeated searches on the ship, she never reappeared. There was no indication she had been murdered and according to her family, she was not suicidal.
6. Ben McDaniel. The underwater caves at Vortex Spring were thrilling for an experienced diver like Ben. But when he went into the cave on August 18, 2010 and did not return, his family and girlfriend feared the worst. Two tanks belonging to him were found at the opening of the cave; most cave divers place their extra takes along the route so they can follow them out. The tanks contained just air, not the specialized gas mix a diver of his experience would have used. He was not found in the cave, and he has never been seen since.