In 1965, began composing soundtracks for the show, "I Spy." This was the first show in television history in which every episode had its own individual soundtrack. Over the course of three years, "I Spy" had 82 episodes, each with an distinctive soundtrack, and Earl Hagen wrote over sixty of them by himself.
Every episode was set in a foreign locale, and Hagen made liberal use of native music traditions. But in the end, global tunes were always married to Hagen's native jazz.