They didn't look like killers. Richard Loeb, an 18-year-old graduate student, was smart, handsome, charming and wealthy. His friend and lover, 19-year-old Nathan Leopold, was a brilliant law student, a published ornithologist, and the heir to a manufacturing fortune. But despite their pedigrees, the duo who considered themselves Nietzschean "supermen" to whom laws did not apply became obsessed with pulling off the perfect crime. They proved sloppy criminals, however. On May 21, 1924, the two men kidnapped and murdered Loeb's 14-year-old cousin, Bobby Franks. While dumping the body in a culvert near their Chicago homes, Leopold dropped his glasses. The perfect plot came undone; within 10 days, both had confessed to the heinous crime. Leopold admitted they had killed for the thrill of it. "A thirst for knowledge," the bookish Leopold said, referring to the experience of murder, "is highly commendable, no matter what extreme pain or injury it may inflict upon others." Not even the advocacy of super-lawyer Clarence Darrow could save them from conviction, though the pair was able to escape the death penalty. Loeb, the ringleader, was killed by a fellow prisoner in 1936; Leopold was paroled in 1958 and moved to Puerto Rico, where he ran a leprosy hospital.
Top 10 Crime Duos
Bankrobbers Bonnie and Clyde met their end 75 years ago May 23, ambushed by police officers outside Gibsland, Louisiana and shot to death. TIME takes a look at more of history's most notorious crime duos.