I was nearly fired from my job because of this movie....
I'll begin with saying that the final 22 minutes triggered something deep in my psyche. The first hour of the movie is laughable, and only becomes interesting when we see "Josh" lurking behind the bushes, watching Megan's friend. Now, I normally have no problems watching horror movies. I have loved watching them since I was a child with my parents, and then by myself as I got older. The final 22 minutes of Megan is Missing are forever etched into my memory. As others have stated on here, what's seen and heard on screen is frightening because it's something that is very real; something that has happened to many people in real life.
To make a long story short, I watched this late at night with a couple friends in my friend's basement. I had to be at work early the next day. I could not sleep at all when I got home from my friend's, as all I could think about was those poor girls and how they got to spend their final hours of their lives.
Because of my lack of sleep, and the fact that I couldn't get the movie out of my head while I was working, my performance suffered greatly. It was so bad, that my boss actually took me into his office and proceeded to tell me that my performance was so poor that he thought my presence there was no longer required that day. I eventually talked him out of sending me home.
It just goes to show how much this movie left an impression on me. It's terrifying to think this is how many people spend the last moments of their lives.