Perry Edward Smith was born on October 27, 1928, in Huntington, Nevada, to rodeo performers John "Tex" Smith and Florence Julia Buckskin. His early life was marked by instability and abuse. After his parents' separation, Smith lived with his alcoholic mother, who died when he was 13. Subsequently, he and his siblings were placed in Catholic and Salvation Army orphanages, where he suffered physical and emotional abuse. Smith's adolescence was troubled; he joined a street gang and engaged in petty crimes, leading to time in juvenile detention homes. At 16, he joined the U.S. Merchant Marine and later served in the Army during the Korean War. A severe motorcycle accident left him with chronic leg pain, for which he consumed large amounts of aspirin. Smith had a keen interest in art, literature, and music, often writing poems and painting while incarcerated.

In 1959, Smith reconnected with Richard Hickock, whom he had met during a previous incarceration. Hickock had learned from a former cellmate, Floyd Wells, that Herbert Clutter, a wealthy farmer in Holcomb, Kansas, kept large sums of money in a safe at his home. On November 15, 1959, Smith and Hickock entered the Clutter residence, only to find no safe and minimal cash. To eliminate witnesses, they bound and gagged the family members. Smith admitted to slitting Herbert Clutter's throat and shooting him, as well as shooting Kenyon Clutter. There is ambiguity regarding who killed Bonnie and Nancy Clutter, with Smith and Hickock providing conflicting accounts.

After the murders, the duo fled, traveling through several states and into Mexico. They were arrested in Las Vegas on December 30, 1959. Both were extradited to Kansas, tried, and convicted of four counts of first-degree murder on March 29, 1960. They were sentenced to death and executed by hanging on April 14, 1965.