What does a scanner see?

I am reading this book by Philip K. Dick called A Scanner Darkly. PKD has written some good books that became movies such as When Androids Dream Electric Sheep that went on to become the movie Blade Runner. He also wrote The Minority Report which became a movie. Now A Scanner Darkly has been made into this cool new movie which is my running favorite: http://imdb.com/title/tt0405296/.

Yesterday the runts and I went to the public library to pick this book up where a police officer became alarmed at the childrens behavior and asked them who they were with when they were discovered running ramshackle through the library then they suddenly bacame sullen and downtrodden when I said they got in trouble.

Anyway I am heavily engrossed in this book and I read almost 50 pages in one day. It is written in the weird style where occasionally the narration is actually heard by the characters in the book. I've never experienced anything like it and it throws you off for a second.

-Aaron