Private notebooks reveal the alleged Georgia school shooter made meticulous plans to kill students and teachers ahead of the deadly tragedy at Apalachee High School.

“Shoot the teacher first,” Colt Gray wrote in a notebook found by investigators in his bedroom, according to testimony from a Georgia Bureau of Investigations official Wednesday.

“Gut shot,” the 14-year-old labeled a stick figure he drew “with a bullet going through their body,” GBI Special Agent Lucas Beyer said on the witness stand. 

The chilling new details were revealed at a hearing Wednesday for Gray’s father, Colin Gray, charged with four counts of involuntary manslaughter, two counts of second-degree murder and eight counts of cruelty to children.

Colin Gray purchased the gun for his son for Christmas last year, and investigators testified Wednesday that for months leading up to the deadliest school shooting in Georgia’s history, Colin Gray purchased a laser sight, tactical vest and ammunition for his son, all while his son’s mental health was in a downward spiral and his mother Marcee Gray implored Colin to keep the weapons away from their son.

A judge ruled Wednesday there is probable cause enough for the case against Colin Gray to proceed.

More new details were revealed Wednesday about how the 14-year-old allegedly concealed the SIG Sauer M400 rifle on his bus ride to the school in Winder, Georgia, in September.

His backpack wasn’t big enough to conceal the whole gun, so the alleged shooter covered it with a white poster board, officials said.

“By a quick glance it appeared that Colt Gray was possibly transporting a school project,” Beyer said.

The alleged shooter attended his first period class and went to second period with the gun still concealed, Beyer said. Twenty minutes later, Beyer said, he told his teacher he was going to see his counselor. Instead, he went to the restroom, put on a pair of yellow plastic gloves and took out the gun, using the poster board to hide it as he walked towards his classroom.

“He appeared to have it wrapped around his lower torso as if to conceal something,” Beyer said.

His second period classroom door was closed so he found another classroom and opened fire, Beyer said, then ran down the hall and continued shooting. In total, two students and two teachers were killed, and nine others injured. 

Colt Gray is charged as an adult with four counts of felony murder. Attorneys for both father and son did not respond to requests for comment.

He also texted both of his parents while sitting in school before the shooting, GBI Special Agent Kelsey Ward told the court Wednesday.

“I’m sorry. It’s not your fault,” he texted Colin Gray at 9:42 a.m. “You’re not to blame for any of it.”

Next he texted his mother, “I’m sorry,” prompting her to call the school to sound an alarm.

Beyer testified that one notebook was recovered from his second period classroom and read aloud from it on the stand.

“Walk from first to the bathroom, so I’ll set my bag down, open it, put on a vest, take a moment or two to stay calm and really think about if I want to do this,” Beyer read from the notebook. “Take out the poster covering the rifle, take out rifle and prop it against the stall. Vest should be on at this point, get out gloves, put them on, they are in your backpack … zip up backpack, check mag slots.”

The alleged shooter was not wearing a vest or hat but had planned to according to his writings.

“Turn on your red dot, aim down at the floor. Make sure your sight is on,” Beyer read. “Don’t shoot anyone in the bathroom. You’ll alert people.” Beyer also said that the notebook revealed he expected to kill between 21 and 26 people.

Ward testified that two more notebooks were recovered from his bedroom.

“One of [the stick figures] appears to have a head wound and the other one is yelling in horror,” Ward testified of the drawing in one of the notebooks. “Then it shows his stick figure again with the word ‘suicide’ and a smiley face written,” she said, adding that then, “he shows the stick figure shooting himself.”

In the second notebook recovered from his room were more disturbing drawings: “It was a drawing of a rifle with what appears to be ammunition coming out of it. And then the word ‘kids’ written past the ammunition.”

The testimony Wednesday revealed more red flags leading up to the shooting. Beyer testified that the alleged shooter referenced the Parkland school shooting to his grandmother around one week before the shooting. 

“If something terrible happened to me or I did something terrible, would you still love me?'” Beyer said he asked his grandmother.