James Holmes was an intensely shy student who had a wry sense of humor, but locked himself away in the days leading up the Aurora theater shooting, colleagues and classmates told the New York Times.
One classmate told the newspaper Holmes texted her in July asking if she had heard of "dysphoric mania."
Dysphoric mania is a form of bipolar disorder that can, in some cases, lead to paranoid delusions.
The friend messaged back, asking if dysphoric mania could be managed with treatment. He replied, "It was," and added that she should stay away because, he said, "I am bad news."
That was the last the student heard from Holmes, the newspaper reported.
Two weeks later, Holmes was arrested in the back of the Century 16 movie theater after, police said, he killed 12 people and injured 58 others in a mass shooting during a midnight screening of the new Batman movie, "The Dark Knight Rises."
It's been more than a month since the shooting, and still Holmes' motives and his actions before the shooting are a mystery.
The Times reported that according to interviews with people who knew Holmes in the months before the shooting, he was a young man struggling with a severe mental illness who more than once hinted of problems to others.
He revealed little about himself, said one graduate student who tried to get to know Holmes better.
The student, speaking anonymously, told the newspaper, "He would basically communicate with me in one-word sentences."
"He always seemed to be off in his own world, which did not involve other people, as far as I could tell," the student said.
Yet something changed in June, when Holmes decided to withdraw from the neuroscience graduate program at the University of Colorado.
Sources have told 7NEWS that Holmes failed an oral exam on June 7 and days later decided to leave the program.
All the while, police have said Holmes was preparing for months before the shooting. He stockpiled 6,000 rounds of ammunition, bought a shotgun and a semiautomatic rifle, two Glock handguns and body armor, they said.
He also set up deadly booby traps, authorities said, that were designed to kill anyone who walked into his Aurora apartment.
The Times reported Dave Aragon, the director of a low-budget movie that tells a story of vigilante justice called "Suffocator of Sins," was contacted by a man calling himself James Holmes of Denver.
Aragon told the newspaper the caller was captivated by the four-minute trailer for the movie that he had watched 100 times.
"He came off as articulate, nervous, on the meek side," Aragon told the Times. "He was obviously interested in the body count."
Holmes was seeing a psychiatrist at CU, sources have told 7NEWS.
Dr. Lynne Fenton met with Holmes several times and told colleagues about his behavior and even contacted CU police.
Call7 Investigator John Ferrugia reported Fenton called members of the CU Denver Behavioral Evaluation and Threat Assessment team, or BETA, in early June to express concerns that Holmes was a threat to others.
One of those BETA members was an officer with the CU campus police, sources said. After Fenton expressed concerns about Holmes and asked for a background check, the officer and the psychiatrist discussed putting him on an M-1 hold, which allowed authorities to hold and evaluate a persons mental health for up to 72-hours multiple sources familiar with the investigation said.
But for unknown reasons, Fenton declined the mental health hold, the sources told Ferrugia.
Sources said since Holmes had no criminal background or warrants, police had no reason to detain him but could have if Fenton had asked for a mental health hold.
Dr. Victor Reus, a professor of psychiatry at the University of California, told the Times dysphoric mania is not uncommon in patients with bipolar disorder.
In severe cases, patients can become highly agitated and caught up in paranoid delusions, Reus said.
Reus admitted he knows nothing about the psychiatric treatment Holmes may have received but said in some cases, psychiatrists prescribe antidepressants for patients with dysphoric mania -- drugs that can actually make the condition worse.
An attorney representing Fenton has repeatedly refused to comment, citing a court-imposed gag order.
Perhaps the answers lie in a notebook Holmes is said to have mailed to Fenton that the university said arrived on July 23 -- three days after the shooting.
The contents of the notebook are still under seal by the court.
Fox News reported that the notebook was "full of details about how he was going to kill."
Answers will eventually come as the trial against Holmes, who faces 24 counts of first-degree murder and 116 counts of first-degree murder, proceeds.
The first testimony in the case is expected in a hearing on Aug. 30.
Read more from the New York Times at >NyTimes.com
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