The man accused of killing a dozen people at a Colorado screening of The Dark Knight Rises wants to know how the film ends, a stunned jail worker reportedly told the New York Daily News.

If he said that to me, it would have been real hard to resist smacking him- witness

James Holmes, 24, “was trying to look like he was sincerely curious,” a person who witnessed the bizarre incident in the jail’s infirmary has told the paper.

“Like he had no idea why there was anything wrong with what he was saying. It was sick ... I think he’s trying real hard to act crazy.”

His eyes glazed and his voice flat, Mr Holmes reportedly asked a jail worker “Did you see the movie?” and then “How does it end?”

He repeated the question when the worker ignored him.

“If he said that to me, it would have been real hard to resist smacking him,” the unnamed witness told the paper.

Another disturbing report surfaced yesterday that Mr Holmes mailed a notebook “full of details about how he was going to kill people” to a University of Colorado psychiatrist before the attack, but the parcel sat unopened in a mailroom.

The spiral-bound notebook was discovered on Monday after the psychiatrist received a package he feared had come from Mr Holmes and police searched the mailroom for suspicious packages, FoxNews.com reported.

“There were drawings of what he was going to do in it – drawings and illustrations of the massacre,” an unnamed law enforcement source told the website.

Among the drawings were gun-wielding stick figures blowing away other stick figures.

It’s not clear how long the package was in the mailroom, or why it wasn’t delivered and discovered prior to Friday’s massacre.One source told FoxNews it had been in the mailroom since July 12 but a second source said that they were unable to confirm that the package had arrived prior to the massacre.

Mr Holmes, who is accused of shooting dead 12 people and wounding 58 others at a cinema in Aurora, outside Denver, is being held in solitary confinement in the Arapahoe County Detention Center.

He was moved to the infirmary for his own protection on Tuesday, the Daily News reported, and was fitted with a black plastic faceguard to stop him from spitting on guards.

The graduate school dropout appeared dazed and disoriented at his first court appearance Monday. He could face the death penalty upon conviction if unable to prove he is mentally incompetent.

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