(ABC News) -- James Holmes, the man who allegedly killed 12 people and wounded 58 at a packed screening of the latest Batman movie, "The Dark Knight Rises," applied to join a Colorado gun range last month, but was rejected by the owner, who found him "creepy."
Glenn Rotkovich, who owns the Lead Valley Range in Byers, Colo., told ABC News that Holmes applied for membership about a month ago via email, but when Rotkovich called him to follow up, he said he got a "bizarre," Batman-inspired voicemail message.
He told his staff not to allow Holmes into the club if he showed up for an orientation.
The gun range owner's reaction adds to a growing portrait of the 24-year-old accused of carrying out the worst mass shooting in U.S. history, and who police say rigged his apartment with dozens of explosive devices set to go off when the door was opened.
Overnight, ABC News obtained exclusive video and photos of Holmes. The video, which was recorded six years ago when Holmes was 18, gives some insight into his life.
In the video, he is standing among his peers at a science camp held at Miramar College in San Diego talking about "temporal illusions."
"Over the course of the summer I've been working with a temporal illusion. It's an illusion that allows you to change the past," Holmes said in the video.
He appears slightly nervous speaking to the group but also extremely intelligent.
This is how he was explaining his mentor's shared interest in fantasy versus reality in the video: "He also studies subjective experience, which is what takes places inside the mind as opposed to the external world. I've carried on his work in dealing with subjective experience."
By most accounts, Holmes lived the life of a normal teen -- with a particular interest in science.
The video shows him being introduced at the seminar as someone whose "goals are to become a researcher and to make scientific discoveries. In personal life, he enjoys playing soccer and strategy games and his dream is to own a slurpee machine."
Though Holmes was apparently a gifted scientist who had received a federal grant to work on his Ph.D. at one of the most competitive neuroscience programs in the country, he was a loner who -- oddly for a young student -- seemed to have no Internet presence.
On Saturday, officials said they have "evidence of calculation and deliberation" in the way Holmes allegedly planned and prepared for the shooting, beginning to buy weapons and ammunition two months ago.
Aurora Police Chief Daniel Oates announced Friday that Holmes had purchased four guns at local shops and more than 6,000 rounds of ammunition on the Internet in the past 60 days.
Holmes received deliveries to the school and his home over that period, police said.
Holmes was enrolled in a neuroscience graduate program at the University of Colorado. On Sunday, officials at the school's Anschutz Medical Campus said they are looking into whether Holmes had items delivered to the school.
"We are cooperating fully with the police investigation. It was mentioned yesterday that deliveries may have come to his work. That is being looked into," university spokeswoman Jacque Montgomery said.
The shooting began shortly after midnight Friday, at a soldout showing of "The Dark Knight Rises." Dressed in full riot gear, Holmes allegedly entered from an emergency exit in the front right corner of the theater before releasing something that witnesses identify as tear gas or a smoke bomb.
From there, he allegedly sprayed the sold-out theater with a storm of bullets, injuring and killing both adults and children.
Police caught him in the parking lot. Holmes, 24, is currently in custody at Arapahoe County Jail.
Some recently released inmates from the jail said Holmes is not likely to get a warm welcome from the other prisoners.
"They're paying really close attention to keeping him separate," Steven Phillips, who was recently released from there, told ABC News. "He's in red, he's in chains, his arms are chained up in like a jacket. When he came in, they said he had a bullet proof vest on over his clothes so somebody wouldn't stab him."
Phillips heard that Holmes is being kept in 23-hour lockdown, one of the most protected types of confinement. He is given one hour outside his cell per day to shower and use the phone.
Jacob Wesson, also recently released from Arapahoe County Jail, said that because Holmes is a murder who killed children, if he was kept with other inmates, they would hurt him. "He wouldn't last," Wesson said.
New pictures emerged overnight of several explosions in a Colorado field where investigators took chemical materials recovered from Holmes' apartment.
Crews reportedly transported the materials by dump truck to the field so that they could be ignited -- and determined if they were in fact explosives.
Federal authorities and local police have now pulled all of the potential explosives from Holmes' apartment after gaining entry and eliminating potentially explosive traps Saturday.
The 800-square-foot apartment contained several trip wires rigged to trigger explosions, police said.
Scattered throughout the living room were 30 explosive devices -- including jars with chemicals and 30 shells with explosive powder -- similar to large fireworks, police said.
Bomb squads carefully neutralized the two main threats at the entrance of his apartment using a "water shot" and remote-controlled robot.
Oates said the suspect's intentions were clear.
"What we're seeing here is some evidence of calculation and deliberation," Oates said.
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