Roberto Arguelles was born on February 18, 1955, in Salt Lake City, Utah. He grew up in a troubled environment, experiencing abuse and neglect. Arguelles had difficulty in school and often got into trouble. As a teenager, he was sent to a juvenile detention center for various offenses.

In March 1992, Roberto V. Arguelles committed a series of violent crimes that would lead to the deaths of several individuals. On March 30, he kidnapped two teenagers, 16-year-old Lisa Martinez and 15-year-old Tuesday Roberts, who were last seen walking toward the Valley Fair Mall. After his capture, Arguelles confessed to stabbing Martinez over 40 times with a wood chisel and strangling Roberts with a rope. He directed authorities to their graves near his stepfather's pig farm in Utah.

Months later, Arguelles confessed to two additional murders. One was 42-year-old janitor Margo Bond, who disappeared in February 1992 and was found dead four months later. The other was 13-year-old Stephanie Blundell, who was killed a month after Bond. Arguelles claimed to have stabbed Blundell to death as well. Although some of the jewelry from Blundell was reportedly shown to other inmates, the police never recovered these items.

In 1997, Arguelles went to trial for the four murders. He quickly announced his intention to plead guilty and requested a death sentence. During the trial, he appeared disinterested and sought to represent himself. Despite claims from his attorneys that he might have mental health issues, Arguelles insisted on being sentenced to death. On June 21, 1997, he received a death sentence, choosing the firing squad as his method of execution.

As appeals progressed, Arguelles was involved in erratic behavior. He attempted suicide in jail and faced health issues, which required medical attention. On November 15, 2003, guards found him unresponsive in his cell. He was diagnosed with a bowel obstruction and later died from this condition. He had not been executed before his death in prison.