The plot: On Halloween in Haddonfield, Illinois, having already shown signs of psychopathic tendencies, ten-year-old Michael Myers murders a school bully named Wesley.

He returned upstairs and began pacing, imagining killing his little sister, he wrote. I don’t know, I’m pretty, I guess, evil…Whatever, I’m sorry. And then I went down and I shot my mom maybe three or four times, but I’ll never forget this. That will be provided, so you don’t have to worry about that right now. In through your nose, and out through your mouth so you don’t hyperventilate, okay?

My sister, she came downstairs and she was screaming and I was telling her that I’m sorry but just to hold still – that, you know, I was just going to make it go away. Jake, what I want you do to is walk outside, but when you’re walking outside, stay visible, don’t walk behind any furniture.

Though Evans is not known to have been suffering from any mental illness at the time, he writes that after the shooting, 'in shock I ran into my room and screamed at the top of my lungs that I am really messed up and that I killed my mom and sister'.

Evans said he also had planned to kill his grandparents at their home across the street and his oldest sister who was there, as well as another older sister who was home from college, according to the statement.

And what happened last night will haunt me forever.'In the last lines of his confession, he wrote: 'I know now though that I'm done with killing.

It's the most dreadful and terrifying thing I will ever experience.

A 17-year-old boy who shot his sister and mother said that watching horror movie Halloween gave him the idea because he was 'amazed at how at ease the boy was during the murders and how little remorse he had'.

The chilling confession spells out in intricate, matter-of-fact detail the thoughts and actions of the 17-year-old in the hours leading up to and during the inexplicable slaying of his two family members.

Though it's discouraging news, being able to expose the problem is the first step toward finding a solution.