Phillip Carl Jablonski was born on January 3, 1946, in Joshua Tree, California. He grew up in a troubled household. His father was an alcoholic who was known for his violent behavior. He abused his wife and children, which created a difficult environment for the family.

In high school, Jablonski met Alice McGowan, and they began dating. After graduating, he enlisted in the Army in 1966. He was sent to fight in the Vietnam War. Jablonski returned to the United States in 1968, and he married Alice shortly after. They settled in Texas, where their relationship took a dark turn. He became sexually violent, and there were instances where he tried to suffocate Alice during their intimate moments. This pattern of abuse led to their separation.

After his marriage to Alice ended, Jablonski started a relationship with Jane Sanders in November 1968. Their relationship also turned violent. He assaulted her on their first date, an incident she did not report. Jane became pregnant, and they moved to California in July 1969 after Jablonski left the military. During their time together, he threatened her with a gun during a sexual encounter. Jane managed to escape and left him in 1972.

In late 1972, Phillip Carl Jablonski raped a woman at knifepoint in her home. The woman managed to escape and called the police. Jablonski was arrested and convicted for this crime.

In 1977, Jablonski met Linda Kimball, and they began living together in Palm Springs. In July 1978, Jablonski approached Kimball's mother, Isobel Pahls, and attempted to assault her. Pahls escaped and did not report the incident. A few days later, Kimball went back to their apartment to gather belongings and was found dead. She had been beaten, stabbed, and strangled. Jablonski was arrested 11 days later and served 12 years in prison for her murder. He was released on parole in 1990.

In 1982, Jablonski married Carol Spadoni while he was still in prison. On April 23, 1991, he murdered both Spadoni and her mother, Eva Petersen, in their home. Spadoni was shot and suffocated, while Petersen was shot and sexually assaulted.

On April 22, 1991, Jablonski killed Fathyma Vann, who was a classmate at community college. Her body was discovered in a ditch, and it showed signs of mutilation. Three days later, he threatened a woman at a rest stop in Wyoming but she escaped. Jablonski was also charged with the murder of Margie Rogers, a store owner in Utah, who was found shot in the head after being assaulted.

He was arrested on April 28, 1991, in Kansas. Jablonski was convicted of multiple murders and sentenced to death. The California Supreme Court upheld his death sentence in 2006. Jablonski died on December 27, 2019, at the age of 73 in San Quentin State Prison.