Joseph Gerard Christopher was born in Buffalo, New York, on July 26, 1955, to Therese, a registered nurse, and Nicholas, a maintenance worker for the city's sanitation department. The only son in a family with four children, Joseph grew up with two older sisters and one younger sister. His father, an enthusiastic outdoorsman and hunter, introduced Joseph to shooting and handling weapons at a young age.

Joseph began his education at Burgard Vocational High School in 1971, enrolling in an automotive mechanics program. Known as a quiet but intelligent student, Joseph excelled in practical courses, though he was not particularly academically inclined. He left school in early 1974 and, after cycling through a series of odd jobs, secured a position as a maintenance man at Canisius College. However, his tenure there ended in 1979 when he was dismissed for sleeping on the job, leading him to move back in with his parents.

As Joseph's life progressed, he began to struggle with mental health issues. Recognizing his deteriorating condition, he sought help in 1978 and tried to admit himself to the Buffalo Psychiatric Center in September 1980. Unfortunately, he was turned away; the staff concluded he was not a danger to himself or others and recommended counseling instead. This decision came at a critical time—just two weeks later, Joseph began a terrifying sequence of events that would later horrify the community.

Joseph Gerard Christopher's reign of terror began on September 22, 1980. Over the course of 36 hours, he murdered four individuals, starting with a 14-year-old boy named Glenn Dunn outside a supermarket in Buffalo. He continued his spree by shooting Harold Green at a fast-food restaurant, followed by Emmanuel Thomas near his home, and finally, Joseph McCoy in Niagara Falls. These actions earned him the chilling nickname, the ".22-Caliber Killer."

Christopher's brutality escalated further when, in early October, he gruesomely killed two men by bludgeoning them and removing their hearts. The body of 71-year-old Parler Edwards was found in his own taxi's trunk, while 40-year-old Ernest Jones was discovered near the Niagara River. These horrific acts added a new layer of fear to his already terrifying spree.

On October 10, Christopher attacked Collin Cole in a Buffalo hospital, attempting to strangle him while expressing racial hatred. Fortunately, a nurse intervened in time to save Cole, though he sustained serious injuries. These murders initially remained unsolved, and Christopher enlisted in the U.S. Army, where he was stationed at Fort Benning.

During a furlough in December, Christopher traveled to Manhattan and continued his spree, stabbing five individuals in a single day, killing four. This series of stabbings in such a short span labeled him the "Midtown Slasher." He returned to Buffalo, where he fatally stabbed Roger Adams and Wendell Barnes.

His violent streak continued at Fort Benning, where he attacked a fellow soldier in January 1981. He was arrested after this incident and, during an investigation, evidence was discovered linking him to the murders. Representing himself in court, he was initially sentenced to 60 years but was later retried and sentenced to life imprisonment after being found competent to stand trial. Joseph Gerard Christopher died in prison from a rare form of male breast cancer on March 1, 1993.