William Clyde Gibson III was born on October 10, 1957, in Raleigh, North Carolina. He was the youngest of four children in his family. His father, William Jr., worked as a foreman for a tree-trimming company. His mother, Jeraline "Geri" Gibson, was a cashier at a Sears store. When Gibson was two years old, the family moved to New Albany, Indiana, where he grew up. In interviews later in life, Gibson stated that he was spoiled and did not experience any abuse or neglect from his parents. However, he also acknowledged that his father was an alcoholic who became combative when drunk.

As a child, Gibson displayed strange behaviors. He had difficulty speaking with others and struggled in school. He preferred to stay at home with his mother rather than interact with other children. Throughout his early school years, he was bullied by his classmates. It was not until the sixth grade that he grew big enough to stand up for himself, but he began to bully others during this time. Gibson often got into trouble for fighting and not following school rules.

Outside of school, he engaged in violent behavior. A childhood friend claimed that he shot another child in the eye with a pellet gun. At the age of 13, he began drinking alcohol and was arrested later that year for stealing a motorbike. His troubled youth continued as he dropped out of school.

Gibson started to commit minor crimes, including drunk driving. Soon after a driving incident, he joined the Army and was stationed in West Germany as a mechanic. While serving, he won awards for marksmanship; however, he also developed an addiction to drugs, including heroin and cocaine. In 1979, Gibson was dishonorably discharged from the Army after stealing a car. He spent a year in prison at Fort Leavenworth, where he once attempted suicide.

After his release, Gibson married an artist in June 1980. However, his marriage struggled after he was diagnosed with infertility. This diagnosis led him to use more drugs, and he reportedly smoked a large amount of marijuana daily.

On October 10, 2002, William Clyde Gibson met 44-year-old Karen Sue Hodella at a bar in Jeffersonville, Indiana. They spent time at various bars together. Later, they ended up at an apartment in New Albany. An argument broke out over prescription medications that Gibson was accused of stealing. In a fit of rage, Gibson punched Hodella in the face and then used a pocket knife to stab her multiple times in the throat. After killing her, he disposed of her body in Clarksville. Hodella's remains were discovered on January 7, 2003.

About three weeks after the murder, Gibson was arrested for driving under the influence. After undergoing withdrawal, a psychiatrist evaluated him and determined he showed mild anxiety but was otherwise sane. Gibson was released from jail, but his criminal behavior continued. On February 21, 2006, he stole a purse from a woman. This theft led to another arrest, and he ended up serving a three-year sentence.

Following his release, Gibson spent time at bars and began a relationship with a woman named Kelly Bailey. Their relationship ended due to Gibson's increasing drug use. In March 2012, Gibson met Stephanie Marie Kirk at a local bar. After a day of drug use and sex, they returned to his house, where they got into an argument over pills. Gibson then raped and strangled Kirk, sexually assaulted her, and buried her body in his backyard.

On April 18, 2012, Gibson attacked Christine Whitis, a 75-year-old friend of his late mother. He raped and strangled her, mutilating her corpse afterward. The next day, one of Gibson's sisters found Whitis' body and called the police. Later that day, Gibson was arrested for drunk driving, and he was charged with Whitis' murder a few days later. He confessed to both Hodella's and Kirk's murders as well.

Gibson was charged with three counts of murder, and during his trial, he described feeling an "evil" presence that compelled him to kill. He was found guilty of Whitis' murder on October 25, 2013, and was sentenced to death. He then changed his plea to guilty for Hodella's murder in a deal that stated evidence from this trial wouldn’t affect other trials. He later received another death sentence for the murder of Kirk on August 15, 2014.

Gibson has made several appeals regarding his death sentences, claiming issues around his confessions. However, the Indiana Supreme Court has affirmed all his convictions. In 2018, he appeared in a documentary about death row inmates and claimed responsibility for many more murders across various states, although these claims have not led to charges.