The concept is interesting, and it's actually rather alarming how easily the antagonist pulls off what he does because it's completely plausible in the real world of today for someone to do exactly what he did. For that alone, it's worth the read.
However, the writing is sometimes very juvenile, and the attempt at character buildup is poor. Honestly, there is no character development, but the author should get a gold star for trying. The attempts to develop the characters is designed to draw up an extremely sympathetic emotional response in one instance and, for the very ending of the novel, shock.
The problem is that, because the writing is inconsistent in reminding the reader who all of the major players actually are, the ending forces you to flip back to the start so you can remember who the final person on the page actually is. Once you remember, though, it's very shocking. No sarcasm there. It is a heart skipping moment.
Read it. It's short and worth the few hours if for no other reason than to make you think.