From 1960 to 1965, the CIA brainstormed at least eight plots to assassinate Cuba's Fidel Castro. According to a report prepared in 1967 and declassified 36 years later, the CIA thought of using cigars, contaminated air, poisoned pills, fungus and a poison-filled syringe to take out the Communist leader. One plot, which sought only to damage Castro's image, suggested placing thallium salt in his shoes, in the hope that his beard would fall out. But one idea stood out above the rest: the plan to kill Castro with a booby-trapped seashell. You see, the dictator was a fan of skin diving, so intelligence agents plotted to place an especially spectacular shell in a reef Castro was known to frequent. The hope was that the shell would be so beautiful that Castro would pick it up and, by doing so, trigger an explosive. Desmond Fitzgerald, the CIA's head of Cuban operations, went as far as to buy two books on Caribbean mollusks. But the elaborate scheme was deemed impractical.