A damsel in distress, a detective, a few bad guys and some treasure -- sounds like the makings of a mystery to me.
The Maltese Falcon is a fun, fast and easy read, a great selection for this year's Big Read. I love a good mystery and this one keeps you guessing right up to the end. (Alright, if you've seen the movie then maybe you're not guessing up until the end) but Hammett still does a good job of leading you one direction and then another.
As much as I love Bogart in the movie, after reading the book I don't think that's who I would have cast in the lead, but I have yet to come up with an alternative.