The Half Sister is a predictable family-drama with a light mystery component. It was still fast paced and a quick easy read. This had a slow build up while the sisters tried to figure out this family mystery. I kept waiting for the "this is it" moment, but it never really happened. I felt like there was a lot of extraneous drama going on that pulled away from the story line and made things jumbled at times. It was a little all over the place, but once I got to know the characters it all seemed to come together. The ending comes at you pretty fast and was a little confusing to me. I wouldn’t necessarily put this in the thriller category. It's more family drama/mystery. I liked this book but didn’t love it.