Thank you to Cemetery Dance for providing a review copy. 
What a ride! Jenny wakes up to find herself in complete darkness with no memory of how she got there. There is nothing for her to do but try to figure out the dimensions of the place she's being held captive and reflect back on her life to figure out who she's being held by. This is a gripping psychological horror novel. I love reading about people's messy lives, and Jenny has quite a story to tell. 4.5 stars, rounded up.