Originally designed as a military device, the vocoder has now become the voice of hip-hop and pop music. It has served both the Pentagon and the roller rink, a double agent of pop and espionage. Music journalist Dave Tompkins traces its incredible history from Nazi research labs to Stalin's gulags, from Hiroshima to Manhattan nightclubs and the Muppets. The result is an amazing chronicle of post-war music and culture, filled with unexpected and surprising encounters with John F. Kennedy, Stevie Wonder, Kanye West and Stanley Kubrick.