Minutes after a 7-year-old boy heard a gunshot silence the screaming between his parents, his father walked into his bedroom and told the boy he had to kill him so “Dad and Mom could be together with God,” a police detective testified Friday.

Hours later, while in custody, the same man asked investigators if he could call his wife and three sons to let them know the “blood moon” was causing his mood swings.

A preliminary hearing on Friday revealed the dizzying sequence of events the night Richard Kirk allegedly shot and killed his wife, 44-year-old Kristine, in their Observatory Park home.

Kirk, 48, has been charged with one count of first-degree murder after deliberation.

Kirk smiled at his and Kristine’s families — who sat together — when deputies led him into the courtroom. Several family members bowed their heads, hiding their tears.

Prosecutors argued that Kirk acted deliberately and, despite his erratic behavior, was still able to remember the combination to the gun safe and retrieve his gun. But defense attorneys said it was clear Kirk was unaware of his surroundings and did not have a grasp of the consequences of his actions.

Kristine called 911 at 9:31 p.m. on April 14, about 30 to 40 minutes after her husband began hallucinating, Denver police Detective Troy Bisgard testified on Friday. Kristine said Kirk had eaten marijuana candy and possibly taken prescription pain pills for his back and was acting in a way she and their sons had never seen before.

Toxicology test later revealed that a small amount of THC, the active ingredient in marijuana, was in Kirk’s system that night, Bisgard said. There were no traces of prescription drugs or alcohol.

She described Kirk clambering in and out of their son’s bedroom window, ranting about the end of the world and asking her to kill him. As she struggled to keep her children in the basement, her husband could be heard screaming in the background, Bisgard said.

More than 12 minutes after she called 911, she started begging her husband to “stay away from the gun” and repeatedly yelled, “Stop it! Stop it!”

“At one point she says, ‘Fine I’ll do it. Just give me the gun,’ ” Bisgard testified, adding that eight seconds later Kristine can be heard screaming.

Two seconds later, what sounds like a gunshot is heard and then silence. At 19 minutes, officers are heard knocking at the door.

The dispatcher who was in charge of relaying information from the 911 operators to officers en route failed to tell the officers that Kirk’s behavior was becoming violent. Facing disciplinary action, the dispatcher who handled the call resigned in June.

When officers arrived, the couple’s two oldest sons sprinted to the patrol car. They told the officer their mom and dad were fighting and they had heard a loud bang.

Struggling to maintain his composure, Bisgard said the youngest son was found in his bedroom, near the living room where his mother was lying dead from a gunshot wound to the head. The little boy told officers, “Dad shot Mom.”

A shell casing was found near Kristine’s body, mixed in with a game of chess that had been set out. A semi-automatic handgun was found 10 to 15 feet away.

An autopsy report later revealed the gun had been fired up against or near Kristine’s right temple, Bisgard said.

Investigators found a partially eaten marijuana candy, an untouched joint and a receipt showing Kirk had bought the items earlier that night at a marijuana store in southeast Denver.

A friend of Kirk’s later told Bisgard that Kirk had recently asked him if he ever used edible marijuana for back pain.

Friends and family also told Bisgard that Kristine said she and her husband had hit a “rocky patch” in their 16-year marriage. Within six weeks of the shooting, Kristine told a co-worker she was scared of her husband after he cursed at her during an argument. The couple went four days without speaking.

But in response to defense attorneys’ questions, Bisgard said some friends said “Things were always good” between the two, and Kirk “never said anything negative” about his wife. During a conversation with her sister, Kristine said the arguments were about “normal marriage stuff.”

The Kirks also appeared to be under financial stress, Bisgard testified. The two had about $40,000 in credit card debt and a $2,580 payment was due to the Internal Revenue Service the day after Kristine died.

Investigators said Kristine was covered by a $340,000 insurance policy.

Denver District Court Judge Elizabeth Starrs found there was enough evidence to continue to trial and denied a request to set bond for Kirk’s release. An arraignment hearing has been scheduled for Oct. 10.

Jordan Steffen: 303-954-1794, jsteffen@denverpost.com or twitter.com/jsteffendp