When it's discovered during a routine autopsy, that the dead man had two hearts, Hood and Rachel travel to Southern California to investigate the medical anomaly. Very quickly Hood realizes that the man didn't have surgery and the second heart has 19 different DNA profiles. Hood concludes the only way this could have happened is that the victim was having stem cells injected which produced an entirely new heart. One of the DNA profiles matches a teenage boy who suffered from a rare form of leukemia: his parents had saved his cord blood. Now his sister is suffering from the same disease and her cord blood has gone missing. Hood and Rachel manage to uncover this elite world of youth-seekers -- wealthy people willing to go to any extent, and expense to look and feel young. They manage to stop the ring peddling stolen stem cells and save the girl with leukemia by recovering her missing stem cells; however, the pursuit of a fountain of youth doesn't end.