In the summer of 1976, a serial killer was on the loose in New York. Now, David Berkowitz is serving life in prison for the crimes and says he doesn’t like thinking back to what he did. David Richard Berkowitz is one of the most notorious serial killers in American history and the hunt for him captivated the world in the late 1970s. He became known as the Son of Sam through letters he had left at crime scenes, and police and the media also called him the .44 Caliber Killer – because of the gun he used. Berkowitz had grown up in New York City and previously served in the army, before his spree which ended in him killing six people and wounding seven others.