In her 1996 confession, Diane Zamora said the murder of fellow high school student Adrianne Jones had been all about love. Zamora, by then a Naval Academy midshipman, told Grand Prairie, Texas, police that when her boyfriend David Graham admitted to having sex with Adrianne, she had flown into hysterics and screamed, “Kill her, kill her!”
The teen’s murder — and the surprising revelations that followed, ending with Graham and Zamora behind bars — will be featured in Monday night’s episode of People Magazine Investigates, on Investigation Discovery.
Here are five things to know about the case.
1. The Victim and Her Killers All Knew Each Other
Adrianne and Graham both went to high school in Mansfield, Texas, where they were both noted for their academics. And, like Zamora, a student in nearby Crowley, Texas, Adrianne and Graham were runners. A crucial difference separated them, however: Adrianne was 16, while Graham and Zamora were 18 — and inseparable as boyfriend and girlfriend.
“You know how growing up, your mom tells you about the perfect guy, the perfect gentleman, and there’s nobody out there like that?” one of David’s schoolmates at Mansfield High told PEOPLE in 1996. “David was. He was one of the last cool guys on earth.”
2. Adrianne’s Death Stunned Her Community
Adrianne’s body was found on Dec. 4, 1995, on a rural county road, less than 12 hours after leaving home the previous nigth. She’d been beaten and shot twice in the head.
When the story of Graham and Zamora’s arrests in her death first broke in the fall of 1996, their friends were disbelieving. The high school sweethearts had seemed so exemplary in every way — high achievers with even higher ambitions.
• Watch our new true crime show, People Magazine Investigates, which continues with an episode on Adrianne Jones’ murder on Monday at 10 p.m. ET on Investigation Discovery.
Graham, then a first-year cadet at the Air Force Academy, dreamed of becoming a fighter pilot. Zamora, who had won a similarly coveted appointment to the Naval Academy in Annapolis, Maryland, had set her sights on being an astronaut. Everything was mapped out, including their wedding date in the summer of 2000, right after graduation.
“I remember being flabbergasted when I heard Diane had been arrested,” a family friend told PEOPLE at the time. “I kept saying, ‘This can’t be the same Diane Zamora. There must be some mistake.’ ”
3. Zamora Was Turned in by Other Cadets
During a late-night bull session in August 1996 with two Annapolis roommates, Zamora confided she had been involved in a murder. (Police had found Adrianne’s body nine months earlier, but the case remained unsolved.) “She said anyone who got between her and David would have to die,” one of the roommates, Jennifer McKearney, later testified. “She said … the girl deserved it … everyone knew the girl was a tramp and a slut.”
When McKearney asked if she had any regrets, Zamora had replied, “No, it had to be done.” Shaken, McKearney and the other roommate went to Naval Academy authorities. Within days, Zamora and Graham were in custody, and each quickly gave written confessions.
RELATED VIDEO: Exclusive clip from Monday’s People Magazine Investigates
4. The Love Triangle Led to Murder
According to Graham’s statement, he offered Adrianne a ride home on Nov. 4 after a cross-country meet. While driving, she directed him to the back lot of an elementary school, where they had a sexual encounter that he said was “short-lived and hardly appreciated.”
That same evening he divulged his infidelity to Zamora. “For at least an hour, she screamed sobs that I wouldn’t have thought possible,” Graham said in his confession. Shortly, though, she regained her composure sufficiently to demand an act of atonement. “The only thing that could satisfy her womanly vengeance was the life of the one that had, for an instant, taken her place,” Graham said, in the oddly stilted language that is apparently his confessional style.
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In her own statement, Zamora reportedly told Graham “that the ‘purity’ of their love could only be restored by killing Adrianne,” one law enforcement source told PEOPLE. Graham insisted to police that he felt powerless to say no. “Diane’s beautiful eyes have always played the strings of my heart effortlessly,” he said. “I couldn’t imagine life without her. … I didn’t have any harsh feelings for Adrianne, but no one could stand between me and Diane.”
5. One of the Killers Maintains Their Innocence
Graham and Zamora were convicted of murder and sentenced to life in prison for Adrianne’s killing, but Zamora — who is no longer in contact with Graham — maintains her innocence.
She spoke to People Magazine Investigates for Monday night’s episodes, from behind bars, describing what she says happened 20 years ago.
People Magazine Investigates airs Mondays (10 p.m. ET) on Investigation Discovery.
• With STEVE HELLING