Mack Ray Edwards was born on October 17, 1918, in Montgomery County, Arkansas. Very little information is known about his early life and upbringing. In 1941, Edwards moved to Los Angeles County, California. The following year, he joined the United States Army Corps of Engineers. In the Army, he trained to operate heavy equipment and served as a combat engineer.

After his military service, Edwards married Mary Howell in 1946. From 1950 to 1957, he lived in several cities in Los Angeles County, including Pico Rivera, El Monte, and Azusa. He was known to keep horses and often allowed neighborhood children to ride them. He also took local kids on camping trips.

In the 1950s, Edwards became a member of the International Union of Operating Engineers. He worked as a heavy equipment operator for the California Department of Transportation and other agencies. He was involved in freeway construction projects during the 1950s and 1960s. In the 1960s, Edwards moved with his wife and their two adopted children to Ralston Avenue in Sylmar, Los Angeles.

Mack Ray Edwards molested and murdered at least six children between 1953 and 1970 in Los Angeles County, California. His criminal activities began with three murders from 1953 to 1956, followed by three more in 1968 and 1969. Edwards stated his crimes were motivated by sexual desires.

In 1970, he kidnapped three sisters, Valerie, Cindy, and Jan Cohen, from their home. Edwards, along with a 15-year-old accomplice, forced the girls to write a note to their parents before taking them to a remote area in Angeles National Forest. The girls managed to escape, leading Edwards to turn himself in to the police. He confessed to the kidnapping and mentioned that he had killed six other children.

After police recovered three bodies, Edwards pleaded guilty to three counts of kidnapping and murder. His trial faced delays due to multiple suicide attempts while he awaited trial. Edwards expressed a desire for the death penalty and was ultimately sentenced to death in 1970. He was transferred to San Quentin State Prison, where he lived in a cell adjacent to Charles Manson's neighbor.

On October 30, 1971, Mack Ray Edwards took his own life in his prison cell by hanging himself with a television cord.