Mike Karr is a fictional character on the long-running daytime soap opera, The Edge of Night. A tireless crime-fighter, Karr was introduced as a cop finishing law school. This character evolved from the earlier Perry Mason character on radio. He then progressed to the District Attorney's office as an ADA, hung his own shingle as a defense attorney for several years, then became DA of Monticello. Karr was played by three actors: John Larkin (radio's Perry Mason) from the show's debut in April 1956 to October 1961, from November 1961 to June 1, 1971, then Forrest Compton from June 2, 1971 until the show ended on December 28, 1984. Mike Karr was the only character on The Edge of Night to last the entire run of the series. Mike appeared in both the premiere episode April 2, 1956, and the final telecast on December 28, 1984.