John David LaDue readily admits he came from a good home and says he was never bullied.
But something in him drove the 17-year-old Minnesotan toward an obsessively detailed plot -- one in which, he said, he wanted to kill his family, set off bombs at a school and then shoot students.
"I think I'm really mentally ill," he told police. "And no one has noticed. I've been trying to hide it."
Transcripts of LaDue's police interviews were released Tuesday. They fill more than 140 pages.
And they offer, in his own words, a chilling glimpse of a teenage boy and his homicidal mindset -- and how far he had wanted to go to act on it.
LaDue was arrested in April before he could carry out his attack. He sits in jail facing numerous charges, including attempted murder. He has pleaded not guilty.
CNN does not usually publish the names of minors charged with crimes but is naming LaDue in this case because his name has been widely reported in his community.
LaDue's mother told police she had no idea he was allegedly plotting to kill his family.
Yet, he said, he plotted right under her nose. He made no effort to hide anything. He told police they'd find three live bombs in a box on the floor next to his bed.
LaDue said his main target was Waseca Junior/Senior High School. But first, he said, he was going to kill his father, mother and sister.
"They did nothing wrong; I just wanted as many victims as possible," he told officers who questioned him.
He said he wanted his attack to be more effective than Adam Lanza's shooting rampage at Sandy Hook Elementary.
He had a low opinion of Lanza, he said, because he shot small children.
"I didn't want to be known as a guy who would go to a place with a bunch of kindergartner(s)," he told police. He thought it more honorable to kill students his own age.
LaDue had studied mass killers in the United States dating back to the 1920s and rated them on the intensity of their crimes, he said.
He had a pecking order of killers he admired. One of his favorites used explosives to kill people at a school.
After slaying his family, the teen, who idealized the Columbine school shooters in particular, allegedly wanted to set a fire.
The arson, however, would only be a diversion to tie up emergency responders while he carried out the main plot at the school, police said.
He'd planned to set off "numerous bombs" during the lunch hour at Waseca Junior/Senior High School, then kill the school resource officer.
Then he'd shoot at students until police officers arrived. He wanted to die but thought it cowardly to turn the gun on himself the way Lanza did.
"I wanted to get taken down by the SWAT," he told officers, according to the newly released documents. "I really wanted to get out of this place."
Luckily, a witness thwarted his plan when she saw the 17-year-old tending to a storage locker, where he kept his stash of bomb-making materials.