David Richard Berkowitz, also known as the Son of Sam and the .44 Caliber Killer, is an American serial killer who pled guilty to eight shootings that began in New York City on July 29, 1976. Berkowitz grew up in New York City and served in the United States Army. Using a .44 Special caliber Bulldog revolver, he killed six people and wounded seven others by July 1977, terrorizing New Yorkers. Berkowitz eluded the biggest police manhunt in the city's history while leaving letters that mocked the police and promised further crimes, which were highly publicized by the press.

A serial killer is a person who murders three or more people, with the killings taking place over a significant period of time between them. The serial killers' psychological gratification is the motivation for the killings, and many serial murders involve sexual contact with the victims at different points during the murder process. The Federal Bureau of Investigation (FBI) states that the motives of serial killers can include anger, thrill-seeking, financial gain, and attention seeking, and killings may be executed as such. The victims tend to have things in common such as, demographic profile, appearance, gender or race. The FBI will focus on particular patterns that the serial killers follow throughout their murders. They will then use on the patterns they find for key clues into finding the killer along with their motives. Although a serial killer is a distinct classification that differs from that of a mass murderer, spree killer, or contract killer, there are overlaps between them.