New York Times #1-bestselling author Robin Cook takes on the cutting-edge world of gene modification in this pulsepounding medical thriller. When a young, seemingly healthy woman collapses suddenly on a New York City subway car and dies upon reaching the hospital, her case is chalked up to a virulent strain of influenza. That is, until she ends up on veteran medical examiner Jack Stapleton´s autopsy table, where Jack discovers some striking anomalies: First, that the young woman has had a heart transplant, and second, that her DNA matches that of the transplanted heart.