Mike and Missy MacIvor seemed to be a charmed couple. The pair were young, good-looking, and loved by those who knew them. Missy, who taught at an elementary school, was pregnant with their first child. But during a massive Florida tropical storm, their bright future together was swept away.
It was on August 21, 1991, that Tavernier Keys, Florida was rocked by a fierce tropical storm. Afterward, family members were concerned when they were unable to reach 30-year-old Mike or Missy, who was 29.
“I had a premonition, an almost impending feeling of doom. I wasn’t sure if it was the storm coming, but I couldn’t put my finger on it," Sharon MacIver, Mike's sister, told producers of "Florida Man Murders," a new Oxygen series, while discussing that dark time.
Missy's coworkers were also worried when she failed to show up for work, so they stopped by the couple’s house, where they could see Mike's feet on the ground inside. They contacted a neighbor, who kicked down the door and called 911 after finding Mike lying in a pool of blood.
"When I walked into the MacIvor crime scene, it was probably the worst homicide scene I had ever seen," Mark D. Andrews, a retired Monroe County sheriff’s detective, told producers.
Mike's face had been taped up, and he was killed by someone standing or stomping on his neck. Missy had been tied up, strangled, and sexually abused. Semen was found on her body, but it didn't match any DNA samples in a database.
Investigators were baffled. Mike and Missy were beloved by their community, but the crime didn't seem random at all. Who would want to murder the two in such a brutal way?
One theory police focused on had to do with Mike's connection to aviation. He had grown up with parents who worked in the field and loved to fly planes. In fact, it was part of the reason the couple moved to Tavernier Keys, a hotspot for pilots.
Mike flew back and forth to Central America often, so police theorized he was possibly involved with drug smuggling. They even traveled to Belize, where he had recently bought a plane in an auction from the government, to confirm the sale was legal.
Police also considered Mike's brother and business partner, James MacIvor, as a potential person of interest — maybe he was the one caught up in drug smuggling — but MacIvor provided a DNA sample that eliminated him as a suspect.
“I knew they were trying to do a job, but I was frustrated. They really upset me. My brother just got murdered, and I said, 'You’re asking me all these questions and I can’t answer them because I didn’t do it!" MacIvor told producers.
The drug cartel theory led absolutely nowhere, and years went by without a break in the case. Eventually, Dayle Hinman, a lead profiler for the Florida Department of Law Enforcement, was brought on. She theorized police were looking at it all wrong: Mike wasn't the target of the attack — Missy was, as she had been sexually assaulted and the killer took his time before murdering her, whereas it seemed Mike’s killing was quick.
“Now we're looking for a different killer, a sociopath, someone who could kill babies," MacIver explained.
So, police questioned the couple’s loved ones again to see if anyone had expressed romantic interest in Missy. MacIver then shared a story she thought was nothing at the time but raised serious red flags for investigators.
The day before she was killed, Missy had told MacIver that the local gas station attendant had been creeping her out. She said he had just hit on her and she had forcefully turned him down.
Hinman had also said the crime scene suggested the culprit was someone with a serious burglary background. This essentially described the man working at the gas station, convicted burglar Thomas Overton.
Overton had been a suspect in a murder the year before the MacIvors were killed after a 20-year-old woman had been dropped off at a Tavernier Key movie theater by her father, then vanished. Overton worked at the theater at the time, and the woman had previously told her father he made her nervous. She was found dead in the woods, but he denied killing her and police had no evidence to link him to the crime.
In April 1993, authorities interviewed Overton, who denied he killed the couple and refused to give a DNA sample. Without the sample, they had nothing connecting him. In Florida, a court can order someone to give a DNA sample if they are arrested on felony charges — so authorities decided to watch and wait.
Over the years, they had many near-misses with Overton: He was once arrested for trespassing in a cemetery at night with a gym bag filled with robbery tools and a surveillance log. And another time a patrol officer spotted him riding his bike alone at night when 15 minutes later, a woman reported an intruder in her house.
"Next time get a dog, get an alarm. You won’t be so lucky next time," was written on the mirror in lipstick.
But finally, in 1996, the break police needed arrived. Overton's friend tipped off police that he was planning a break-in, so they set up a sting and caught him in the act. Overton was carrying a weapon, and it's a felony charge for a convicted felon to be armed during a robbery. They could finally get the court-ordered DNA sample, although the process took months.
Overton wasn't ready to give up just yet, though. While waiting in jail, he obtained a razor blade and cut his own neck. The plan wasn't to die — he wanted to escape while being transported for medical attention. Unfortunately for him, EMTs were brought in to treat him instead, and the scheme failed.
Even worse for him, he left a lot of blood on the jail floor. He had unwittingly handed authorities his DNA sample they’d sought. And it was a match to the semen found on Missy’s body.
In 1999, Overton was found guilty of murdering the young couple and their unborn baby. And he apparently made for an unsettling presence in the courtroom.
"He looked like Hannibal Lector,” Sharon told producers of the trial.
After he was sentenced to death, Overton made one final chilling gesture.
“I will always remember this. He turned around and looked at the crowd and he smiled. He did this stare-down with the families of the people he had killed,” Bill Becker, a retired Florida Keys News Radio reporter, told producers.
Overton has tried repeatedly to appeal his sentence, the Sarasota Herald-Tribune reported in 2012. His attempts have been unsuccessful.
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