Leonard Freeman was an American television writer and producer whose most famous achievement was the creation of the CBS television network series Hawaii Five-O in 1968, the show was remade in 2010. He appeared in a 1953 episode of the TV series, The Lone Ranger.
The show ran for twelve seasons. At the time that was a record for a crime drama. In 1960, he wrote for the series Route 66; in 1962, he produced The Untouchables. In 1967, he produced the Clint Eastwood western film, Hang 'Em High. A decade earlier, he wrote scripts for the syndicated Men of Annapolis.
Freeman died in 1974 during the sixth season of Hawaii Five-O because of complications from heart surgery.