William Adams Hickman was born on April 16, 1815, in Warren County, Kentucky. At the age of four, his family moved to the Missouri Territory. In 1832, at just 17, he married Bernetta Burchartt. By 1838, Hickman had converted to the Church of Jesus Christ of Latter-day Saints (LDS Church) after interacting with members traveling through Missouri. He was baptized by John D. Lee in 1839. Hickman became closely associated with church leaders, serving as a personal bodyguard to both Joseph Smith and Brigham Young. He was reputedly a member of the Danites, a secretive group within the church.

In 1849, Hickman arrived in Salt Lake City, Utah, where he established a homestead. He became deeply involved in the community, practicing polygamy and fathering numerous children. By 1854, he was appointed sheriff and county prosecuting attorney, assessor, and collector in Green River County. That same year, he was elected to the Utah Territorial Legislature.

Hickman's life took a darker turn as he became involved in violent acts, many of which he claimed were under the orders of Brigham Young. In his 1872 autobiography, Brigham's Destroying Angel, Hickman confessed to multiple murders, including the killing of Richard Yates during the Utah War. He detailed his participation in the Provo River Massacre, where he claimed to have killed the Timpanogos chief, Old Elk, and brought his head back to Fort Utah.

In 1871, Hickman was arrested for the murder of Richard Yates. While in custody at Fort Douglas, he wrote his autobiography, confessing to several murders and implicating Brigham Young in ordering these acts. Despite his confessions, Hickman was never convicted, as authorities hoped to use his testimony against Young. However, no charges were ever brought against Young, and Hickman was eventually released.

Following his release, Hickman lived as a pariah, shunned by both the Mormon community and broader society. He died on August 21, 1883, in Lander, Wyoming.