Batman Rises

I'm sure most of you have heard of the shooting at the Batman Rises premier in Colorado by now. And I'm sure that some of you know who the shooter was. But, for those of you who don't know who he is, his name is James Holmes. He is believed to have a genius IQ. People who knew him described him as a loner and intelligent. Now, if someone described his personality to you and you had no idea that he shot up a movie theater, you'd assume that he's a very well rounded man, right? Well, regardless of what you think, that's exactly what I thought.
Which made it all the more unbelievable that a person like him would do such a thing. For the past week, I've been trying to figure out his motives. It's not like he did this spontaneously. It seems like he's been planning something crazy like this, considering he booby trapped his apartment. I'm just dying to know what drove him over edge. What was the thought process or the series of events that led him to do something like this.
I'm not only purposely trying to psychoanalyze James, but I'm looking for reassurance. Reassurance that normal people don't just snap and commit crimes of this magnitude. I'm just afraid that any one of us normal people walking down the streets, or grocery shopping, or bringing in the mail, or doing any other mundane thing won't just let insanity take over so easily. I'm afraid that some of us might be clinging to the edge of reason.