Patrick Macnee, the British-born actor best known as dapper secret agent John Steed in the long-running 1960s TV series "The Avengers," has died. He was 93. Macnee died Thursday of natural causes with his family at his bedside in Rancho Mirage, his son Rupert said in a statement. The clever spy drama, which began in 1961 in Britain, debuted in the United States in 1966.