The Firesign Theatre was an American surreal comedy troupe who first appeared on November 17, 1966, in a live performance on the Los Angeles radio program Radio Free Oz on station KPFK FM. They continued appearing on Radio Free Oz, which later moved to KRLA 1110 AM and then KMET FM, through February 1969. They produced fifteen record albums and a 45 rpm single under contract to
Columbia Records from 1967 through 1976, and had three nationally syndicated radio programs: The Firesign Theatre Radio Hour Hour [sic] in 1970 on KPPC-FM; and Dear Friends and Let's Eat! on KPFK. They also appeared in front of live audiences, and continued to write, perform, and record on other labels, occasionally taking sabbaticals during which they wrote or performed solo or in smaller groups.
The Firesign Theatre was the brainchild of Peter Bergman, and all of its material was conceived, written, and performed by its members: Bergman, Philip Proctor, Phil Austin, and David Ossman. The group's name stems from astrology, because all four were born under the three "fire signs": Aries, Leo, and Sagittarius. Their popularity peaked in the early 1970s and ebbed in the Reagan era.