A former Athens man and his girlfriend have pleaded guilty to a grisly 2015 double murder in Nashville and will each serve at least 51 years in prison before they can qualify for parole.

Although the case is now closed without a trial, the detective who oversaw the case told The News Courier he would still like to talk to Brandon Griswold, 22, and Whitney Gray, 23.

In accordance with the plea agreement, Gray and Griswold each pleaded guilty to two counts of first-degree premeditated murder for beating and cutting the throats of their roommates — Preston Claybrooks Jr., 24, and his longtime girlfriend, Alexandra Grubbs, 23. The murders occurred Sept. 21 while the couple slept at Howe Garden Apartments at 1921 Greenwood Ave. on Nashville’s east side. The victims had to be identified by their tattoos because their skulls were crushed and their faces were unrecognizable, an official said.

Criminal Court Judge Monte Watkins sentenced each to one life term in prison.

Griswold and Gray opted for the plea agreement to get the chance of being paroled after 51 years, the minimum life term allowed by the Tennessee Department of Corrections. The state, as represented by the district attorney’s office, had planned to seek life sentences without the possibility of parole when the two were set for separate trials, Sept. 25 and Oct. 9, respectively.

“I believe there was an overwhelming evidence, and they both confessed,” said Nashville Detective Mike Roland, who led the investigation into the murders. “They implicated themselves and each other. I am guessing they felt taking life with a chance for parole was better than without.”

Gray of Oklahoma and Griswold, a graduate of Athens High School, confessed to the crime. They said they killed the couple to get out of a $650 heroin debt. Gray and Griswold confessed to beating the couple — Gray with a hammer and Griswold with a music stand. Each told investigators the other cut the victims’ throats. Evidence later indicated Griswold was likely the one who did so. Gray and Griswold wrapped their roommates’ bodies in bedding and stuffed them in a utility closet in the apartment. They moved the victims’ blood-soaked mattress into their own room, covered it with towels and their own foam mattress topper and slept there for a few days. Gray went to work two hours after the killings and worked all but one day that week before the bodies were found and they were captured.

When Claybrooks’ mother could not reach him after several days, she went to the apartment Sept. 26 and then called authorities. Roland testified during their preliminary hearing that upon approaching the apartment it smelled like death.

The detective told The News Courier the crime was so senseless, he would like to know if there is more to the story.

He said the plea agreement prevented the accused from possibly being acquitted at trial or of being convicted of lesser charges than murder. He said he was pleased with the agreement because it spared the families of the victims.

“All of that stuff does not really matter except what is best for the families of the victims,” Roland said. “They won’t have to go through the whole process. It is very hard on them. There is an overwhelming emotional aspect, including pictures showing their injuries and descriptions of how they were killed.”

Roland said the murder was horrible.

“They beat this couple to death,” he said. “That is not something a family should have to listen to. It was a total senseless killing.”

Roland said he hopes the families of the victims can take some comfort in knowing the people who killed their loved ones will serve at least 51 years in prison.

“Nothing will give them 100 percent comfort because it won’t bring their loved ones back,” he said.

Two young children of Claybrooks and Grubbs are living with relatives.

Roland also expressed sympathy for the families of Gray and Griswold.

“It is a shame the suspects’ families had to go through this,” he said. “This can’t be a reflection of these parents. Both families were very cooperative, under the circumstances. They have their own crosses to bear, I suppose.”

Roland said the case was among the Top 10 strangest in his career, which has spanned 31 years, including 26 as a homicide detective.

Although he was recognized by the Nashville Police Department for his efforts on the case in 2015, he considers it a group effort.

“It’s a group effort; everyone pitches in,” Roland said. “Everyone did a good job, from the precinct detectives to the patrol officers at the scene. We have a good group here. I just happened to be the person who had to put it all together.”