I've seen the sequel to this movie, but never the original movie and I'm not sure I've ever read anything by Lois Duncan at all, so this was a lot of fun.
I think I might have really loved it (and probably scarfed down the rest of what she has written, which appears to be quite a bit) had I picked it up when I was a bit younger, but this was still an enjoyable ride.
The characters were a bit thinly painted for me, but there was enough there to give a clear picture of each and they felt distinct. I was rooting for them not to die, which is sometimes more than I manage in a thriller, so that was well-done.
I was kind of expecting the twist that he was(show spoiler)
but was thrown by the sudden reveal that he was actually(show spoiler)
I actually didn't see that bit coming.
This was decently suspenseful throughout. It does feel a bit strange, however, because the book both started and ended in such a way that I was left feeling like I was missing a chapter. It's not that things are not wrapped up in a tidy little bow (I like that, actually), but that there is almost nothing that happens after the big confrontation. There is no wrap-up, and there is very little build-up before things start either. I'm not sure how I feel about that--it almost feels too edited.
I'll probably pick up another book by Lois Duncan simply because they are quick and interesting reads and I feel pretty confident I will like it, if not love it.