I found this book a bit weak. I googled Dean Koontz and expected to find that he'd been writing for a couple of years at the most. Instead it turns out that he's been writing for decades. Thus furthering my astonishment at the low quality of the writing.
The premise is hugely exciting: "If tyou don't take this note to the police, I will KILL a lovely, blonde school teacher. – If you do take this note to the police, I will instead KILL an elderly woman."
Now what would you do? You can't not take the note to the police, but then everyone would think that you just wanted to condemn the old woman to die, rather than the pretty woman. Sadly, that's where the exciting plot stops. The rest of the book is strung together strands of story, which seem to have no connection with each other.
The ending, I'll admit is surprising, but only, because it is based on the fact that something entirely unbelievable happened beforehand. I know that I'll be annoying a lot of Dean Koontz fans here, but I'm sorry, I just didn't like it. 3 stars.