Monster by Frank E. Peretti
Anyone who has read anything from Frank Peretti knows there is a plot behind the plot. The books start out with a reasonable storyline and move quickly into something that you are not quite sure is real. You may think 'this' is what is happening, but near the end, you find it was actually 'that' which was happening. These twists keep you wanting to read quickly to the end and find the next book he has written.
This book starts out as a simple camping trip among friends but on the first night, the trip's organizer watches as something carries his wife off into the woods. Although he got a glimpse of something huge and hairy, he could not say for sure if what he saw was real or something from his nightmares.
Very fast paced and intricate in detail, this book will keep you on the edge of your seat. I found I had to fight not to read the end before it's time, because with Frank Peritti's books you have to know the ending few sentences is what pulls the whole book together in one big 'Aha' moment. Excellent read.