Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Good, tight story line

This novel has a gripping story line. If you want a thriller/mystery novel that really pulls you in and takes your mind off of your every day life, this would be it. I especially like the way the writer brings Berlin to life, as it was between the two world wars. I wouldn't categorize this as historic fiction, yet the solid re-creation of Germany during the 1920's and 1930's seems to be very well researched.