Melissa Jo Sermons, a woman involved in the rodeo culture and working with horses, went missing on May 3, 1992, in Lakeland, Florida. She was last seen attending a rodeo in Dade City with 31-year-old Elwin Lawrence "Larry" Costine Jr., who won a team roping contest with a friend and split the $350 prize. Sermons and Costine went to breakfast with a friend at 2:00 a.m. the next day and reportedly went to Costine's home at 4:15 a.m. However, Sermons never returned to her own residence and has not been seen since.

Sermons and Costine's families both filed missing persons' reports with law enforcement when they did not show up for work the next day. Costine's body was discovered nude and shot multiple times in the head and back in his trailer home in Lakeland two days after he and Sermons were last seen. One of his guns was missing, but there was no evidence of a struggle or robbery at the scene. His bed had not been slept in, and there was no trace of Sermons inside the residence.

Investigators believed initially that Sermons might have been involved in Costine's killing, but Costine's family always believed she was innocent. There were reported sightings of Sermons alive and well at truck stops in Florida, Kansas, and Texas since her disappearance, but investigators do not believe these stories are reliable.

In July 2013, authorities named Danny Cerezo, who had previously dated Sermons and lived with her for about a year, as a suspect in Costine's murder and Sermons's disappearance. Sermons had ended the relationship with Cerezo in April 1992 and moved out of his house. Cerezo kept in touch with Sermons's family after the breakup and asked about her other relationships. The day before she disappeared, Sermons spoke to Cerezo on the phone and told him she was dating Costine and did not want to see him.

Police stated they had physical evidence that linked Cerezo to Costine's shooting. However, he has not been charged in either the murder or Sermons's disappearance, and both cases remain unsolved.