There are two key features in successful mystery thrillers: context and plot. In my opinion, context is often the most informative and dramatic element. This book is about two young women in two time-lines: THEN as high school students, and NOW, as post-doctoral researchers in a University medical research laboratory. Given my own background as a biomedical researcher, clearly the context is novel and appealing, the description of lab smells, the equipment, everything is described perfectly. But this is a book about relationships, in particular a friendship complicated by academic competition. And there are dark secrets: a key phrase repeated in the book is “You don’t have a self until you have a secret”. A key progression from dark secrets are lies and then paralyzing “Crime & Punishment” type guilt. Finally, this is a book about women. Highly recommended. Thanks, Karen, for this book suggestion.