The Living Blood by Tananarive Due is an exceptional supernatural thriller with multiple plot lines that are 
carefully interwoven. Initially we follow Dr. Lucas Shepard who discovers that a clinic in Africa has a treatment that cures severe illnesses such as leukemia, the disease that is killing his only son. In one plot line we follow this rogue doctor to Africa in his quest to obtain the cure. In other plot lines we follow Jessica, Dawit, and Fana who are an immortal family. Jessica and her sister run the clinic that Dr. Shepard seeks, and Fana is the daughter of Jessica and Dawit. Fana is a very special three-year old immortal. In this well constructed book we see the forces of good and evil go against each other as well as a division between humans and a group of immortals called the Life Brothers, the group that Dawit is a member. I do not want to say more about the plot, but I recommend that you try this book if you enjoy a well written supernatural thriller.