Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Had a hard time putting this book down

For a few nights, I stayed up way too late reading this book. It has a nimble, imaginative plot that grabbed my interest early and held it to the end. The story juxtaposes the present and the past in a way that might seem implausible. But Gershon makes it work extraordinarily well. Readers also get a fascinating look into modern medicine.