Police officers escort American accused (and ultimately convicted) serial killer David Berkowitz (left), known as the Son of Sam, into the 84th precinct station, New York, N.Y. Aug. 10, 1977. Credit - Robert R. McElroy—Getty Images

The serial killer’s voice in previously unreleased 1980 recordings provides the hook to director Joe Berlinger’s documentary, which also offers interviews with detectives, survivors and others connected to or obsessed with the case.