John Larkin (April 11, 1912 – January 29, 1965) was an American actor whose nearly 30-year career was capped by his 1950s portrayal of two fictional criminal attorneys – Perry Mason on radio and Mike Karr on television daytime drama The Edge of Night. After having acted in an estimated 7,500 dramatic shows on radio, he devoted his final decade to television and, from April 1962 to January 1965, was a key member of the supporting cast in two prime-time series and made at least twenty major guest-starring appearances in many of the top drama series of the period.