Man Killed His Ex-Wife, Then Let Their Children Play With Her Burned Bones

For three siblings in Oklahoma City in 1990, Christmas would never be the same after their mother mysteriously disappeared, only for her body to turn up months later in the most unexpected place.

December 7, 1990 was a normal day for Janet Dennis, a divorcée with three children — at least, at first. She enjoyed Friday dinner with her kids and decorated the house to celebrate the holiday season. Her oldest son, 12-year-old Tad, had a wrestling match at school the following morning, and Janet was known for never missing a school event. However, on Saturday morning, Tad woke up early and went looking for his mother, only to find she wasn’t in her bedroom and her car was missing from the garage.

At the time, he didn’t worry; he assumed his mother had gone to get snacks for the wrestling meet and he settled in to wait for her return. He had no idea the night before was the last time he’d ever see his mother alive.

“I sat there and waited for a little while, but she never came back,” Tad Dennis, now an adult with children of his own, told Oxygen’s “Buried in the Backyard,” airing Thursdays at 8/7c on Oxygen.

When night fell and Janet still hadn’t appeared, Tad’s father and Janet’s ex-husband, Leroy Dennis, took his concerns to the Oklahoma Police Department, who assured him Janet would likely return at some point over the weekend, as was common in most missing person cases. However, when Janet failed to return home by Monday, police began to take her disappearance more seriously and traveled to her home to interview Leroy.

Leroy said the last time his children had seen their mother was on Friday night, when she was wearing jeans, a red top, and a gold necklace. He also claimed he and his ex were on good terms despite the divorce, and insisted he’d been on his farm at the time of his ex-wife’s disappearance, an alibi that was supported by his mother.

When police searched the home, they found no evidence of foul play. Janet had simply vanished, as had her purse and her car.

“It almost appeared that she had just left,” Jerry Jones, Undersheriff in Dewey County, told producers.

Meanwhile, Janet’s family was wracked with anxiety due to the lack of answers.

“We knew something wrong. We knew something had happened to her. We just didn’t know what it was,” Tina Bloomer, Janet’s cousin, said.

Police zero in on two suspects.

Investigators’ next step was to speak to Janet’s father, Arthur, who reiterated it was extremely unlikely for Janet to abandon her children. However, it was his comments on his daughter’s love life that piqued investigators’ interest: He said he’d never liked Leroy, and revealed his daughter had gotten a new boyfriend, Jim Umbenhower, after the divorce. Umbenhower had been to Arthur’s house recently, where he got a key to Janet’s home and went to search the home while Leroy and the children were away, Arthur revealed.

Unsurprisingly, police soon zeroed in on Umbenhower, who was an active member of the military, as a suspect.

“Jim wanting to get into the house after Janet went missing was very strange,” Lt. Det. Craig Gravel of the Oklahoma City Police Department told producers. “We didn’t know what he was searching for, but this was bizarre behavior.”

Shortly afterward, Umbenhower reached out to police and agreed to come in for questioning the following day. Before that could happen, though, airport police discovered Janet’s car in their parking lot and investigators rushed to the scene to examine it.

They found the trunk was filled with toys that were likely purchased as Christmas presents for the children. Unable to find any logical reason for Janet to have bought Christmas presents for her children, only to leave the toy-filled car at the airport without warning, police’s suspicions that something terrible had happened to her were seemingly confirmed.

Then, before police could leave the scene, their main suspect Umbenhower arrived without warning, shocking detectives. No one understood how Umbenhower knew where Janet’s car was — he claimed he’d simply been driving around parking lots, searching for Janet’s car.

Unsurprisingly, police weren't convinced Umbenhower's presence was a coincidence. They asked him about searching Janet's house after her disappearance, and he claimed he was simply interested in retrieving some old love letters he’d written in order to keep their relationship private, which Janet had always requested. He then turned the box of love letters over to police. 

Meanwhile, police began digging deeper into Janet’s life by interviewing her colleagues, who said prior to the divorce, Leroy had been very controlling of Janet; he didn’t like for her hair to look nice or for her to wear jewelry, which made Janet unhappy. She’d been much happier with Umbenhower, her co-workers said.

Police were then met with another bombshell: In direct contradiction with Leroy’s claims, Janet’s co-workers said her divorce had been far from amicable, and that Leroy would go to her house and argue with her in front of their children. They also said Leroy was adamant about getting full custody of the children which, again, contradicted Leroy’s claims he was fine with Janet having full custody of their kids.

“In a heated divorce, you never know what someone’s capable of,” Gravel said. “But in Leroy’s case, he didn’t have custody of his children, and now his ex-wife, who he still loves, has another man in the house, so that’s a good recipe for a murder.”

Polygraph tests and a shocking VHS tape provided more questions than answers.

As police began to piece together what may have happened, Jerry Jones, undersheriff in Dewey County, reached out to the Oklahoma City PD after seeing Leroy on the news pleading for any information that could help with the case. Because Leroy lived on a farm in his jurisdiction, Jones offered to help with the investigation in any way he could. He also told police there were rumors floating around town that Leroy, who was generally not well-liked by his neighbors, was actually responsible for Janet’s disappearance.

Police, now more suspicious of Leroy, asked him to come in and take a polygraph test. Leroy agreed and he stuck to his story: He’d gone to the store that day to buy grain before returning home and spending the rest of the night there. The results were inconclusive, and when police asked him if he would submit to another test, Leroy refused and claimed he didn’t want to sit through it again because he had heart problems.

Leroy, Janet and Tad

In the meantime, authorities began interviewing those who knew him. One neighbor recalled seeing numerous large fires on Leroy’s property around the time Janet had disappeared, but because the fires took place before Janet vanished, police didn’t think much of it at the time.

As the investigation wore on, Umbenhower came down to the station to take a polygraph test, and after a six-hour interview, the results were in: Umbenhower had failed.

Police also learned Umbenhower had been living with a different woman at the time of his relationship with Janet; he claimed he’d been planning to break up with that woman and begin a new relationship with Janet. Despite their suspicions, police did not have any evidence to justify taking Umbenhower into custody. However, soon after, police received yet another call from Leroy, who told them some of Umbenhower's belongings were still in Janet’s house, so investigators rushed over to perform another search of the property for clues.

They soon found a box of men’s toiletries in the bathroom that reportedly belonged to Umbenhower and in the bottom of the inconspicuous box was an unlabeled VHS tape, which they confiscated and took back to the station.

Investigators were shocked by what they saw on the video: It was sexual in nature, and it showed a woman being restrained and burned. Police asked Umbenhower if the tape belonged to him, but he denied it and claimed he and Janet had never watched pornography together. Still, police called him in to take a second polygraph test. Umbenhower continued to claim he loved Janet and was not involved in her disappearance, and this time around, he passed the test. Police chalked up the discrepancy in the two test results to Umbenhower having been sick at the time of the first test, and they then began to focus more on Leroy.

The truth, devastating and terrible, finally came out.

It was two months after Janet disappeared when Leroy’s neighbors, the ones who’d seen the fires on his property, contacted police with a bombshell claim: While they initially thought the fires had taken place the week before Janet disappeared, after checking their calendars, they’d realized the day they’d seen the fires was actually the morning after Janet was reported to have vanished.

“This was huge,” Gravel recalled to producers.

Following that revelation, investigators began searching Leroy’s farm with renewed vigor, this time suspecting he may have burned evidence somewhere on the grounds. They were right: On February 14, 1991, investigators were combing a burned-out, bushy area when they made shocking discovery. Amid the overgrowth were what looked like pieces of bones that had been burnt and left lying in the charred grass.

Then, an anthropologist discovered what they believed to be pieces of a human skull. They also found a gold necklace that had also been burned, which matched the description of what Janet was reportedly wearing on the last day she was seen alive.

Investigators then arrested Leroy for the murder of his ex-wife.

“It was unimaginable,” Tad recalled. “It was hard to realize that my dad had been charged with my mom’s murder, because I loved my dad and in my mind, at that point, I did not think that that was possible, but in actuality, it was reality, and you start to realize that she’s never coming home.”

The slain woman’s son recalled unknowingly playing with his mother’s bones.

Several days after the gruesome discovery on Leroy’s farm, testing confirmed the charred human remains did indeed belong to Janet. Authorities were never able to conclusively state how she’d died — still, police believed they knew what happened: They believed Leroy had snuck into Janet’s house that night and quietly abducted her. He then took her to a house he owned nearby, left her there, went back to Janet’s house, drove her car to the airport to abandon it, and traveled back to Janet’s house in a taxi. He then used his car to drive back to his other house, where he retrieved Janet, who may have still been alive at that point, and took her to his farm in Seiling, where he killed her, likely with a blow to the back of her head. He then burned her body.

Leroy stood trial for Janet’s murder in March 1992, more than a year after he killed her. During the trial, the jury heard a shocking revelation from Tad: He recalled he and his siblings had played with bones they’d found on his father’s farm, bones Leroy claimed belonged to a possum. Unfortunately, that was not the truth: The bones were, in all likelihood, that of the children’s slain mother.

What Tad revealed on the stand shook investigators to their core.

“I don’t think I’ll ever get over it, finding out that that man took his kids out there and played with their mother’s bones,” Jones said. “That just is beyond fathomable to me.”

After deliberating for mere hours, a jury unanimously found Leroy guilty of murder and he was sentenced to life in prison without the possibility of parole. His children have since gone on to honor their mother by celebrating Christmas, which she loved.

“To this day, I still feel like she’s definitely with me in my heart,” Tad told producers.

For more on this case and others, watch “Buried in the Backyard” on Oxygen on Thursdays at 8/7c or stream online any time at Oxygen.com.