able to corroborate. but this one really kind of surprised me. a book was all of a sudden found at a flea market in north carolina. and we are 100% certain, based on handwriting analysis, it was his diary. >> may 3rd, 1967. you've got to project your vision before you. you must make sacrifices of time and effort. >> to go back and look at some of the dark writings that he was doing, it was clear to us that this is not something that snapped that night. he was really heading in a downward spiral for about ten years before he commits the murders. >> as the years go by, his writing becomes more disjointed.