Gilmore had bought a blue Mustang from Val Conlin, a used car dealer, but it had problems and often wouldn't run. He still owed on that but he'd seen a ten-year-old, overpriced white truck on the lot that he really wanted. The dealer said no way, not unless he found himself a co-signer. That frustrated Gilmore. By hook or by crook, he intended to have that truck.
To his mind, there were always ways of getting money. He'd already stolen some merchandise to sell. Then he managed to collect a bag full of guns—-nine of them. He gave one to Nicole, she later told police officers, showed her the rest, and said he intended to sell whatever he could. Nicole's interview for A&E is the best source of information for what happened in those final days, along with Gilmore's own documented admissions. Each person who saw him over the next few days later gave interviews on film as well.
Gilmore had scared her. He'd already shown a violent side, she later related, and now this. She didn't know what to do.
Gilmore had moved into her rented home in Spanish Fork, near Provo, but things weren't always so good. He often took a drug, Fiorinal, for headaches and he drank all the time, which created sexual dysfunction, an inability to think clearly, and a great deal of frustrated anger. He was impulsive and demanding, and there were times when Nicole was actually afraid of him, though she loved him. Once when he'd picked her up she'd had the feeling of an evil presence emanating from him. She thought he might be the devil, and there were times when he acted like he was. He even claimed he knew Charles Manson. Finally it all just got to her. She just took her two children and went to live in an apartment five miles away.
Gary went looking for her. He was in a state. She wasn't going to run out on him. He told his cousin Brenda he might just kill her. But he couldn't find her. On top of that, he was now deeply in debt with no clear way out...except the only way he knew. He'd been free less than three months and already he couldn't cope.
Mailer interviewed the families of Gilmore's victim's and Gilmore's friends to put together the following accounts:
On Monday, July 19, 1976, Max Jensen went to work as usual at the self-service gas station in Orem, Utah. His shift went from 3 in the afternoon until 11. He was just there until he could find a job that paid more so that he and his new wife could get a little security.
At around the same time that Max was going through the routines of his job, Gilmore learned that no one would co-sign on the truck for him, so he insisted that he himself could pay it off within a few weeks. Conlin assured Gilmore that he would repossess the truck at once if the payments weren't made. Then Gilmore left with the truck and headed toward Nicole's mother's house. Nicole wasn't there, but her mentally unstable younger sister, April, had a crush on Gary and was happy to go for a ride in his new truck. She told him she wanted to stay out all night. Angry and hurt by Nicole, as he later said in letters to her, he was pleased to oblige.
Around 10:30 that evening, he told April he wanted to make a phone call. He left her in the truck and walked away. She had no idea where he was going.
Gilmore went around the corner, out of her sight, and into the Sinclair service station. He spotted the attendant and quickly saw that no one else was around. He walked up to the man, whose nameplate read "Max Jensen" and pulled out a .22 Browning Automatic. He instructed Jensen to empty his pockets, which the young Mormon quickly did. Then he told Jensen to go into the bathroom and lie down on the floor with his arms under his body. Jensen got into the position. He was obeying everything that Gilmore said.
Then inexplicably, Gilmore put the gun close to Jensen's head. "This one is for me," he said, and fired. Then he placed the muzzle right against Jensen's skull and shot him once again, this time "for Nicole."
To his surprise, the blood spread fast and got on his pants. He turned around and left the gas station, not even noticing the wad of cash on the counter.
His next move was to take April to see a movie, "One Flew over the Cuckoo's Nest." Then they went over to Brenda's. She thought Gilmore was strangely agitated. He had some clothes that he didn't seem to want her to see. He didn't stay long and she couldn't get over the feeling that something was up.
Without further explanation, Gary drove off with April and they got a room at a Holiday Inn. While they slept, the hunt began for Max Jensen's killer. Around 11:00 p.m., a customer had found the body.