Rick Hayden and Laura Fanning of Panacea return, looking for the missing link. Rick's brother, Keith, a prominent zoologist at NYU, liquidated his assets, purged his research, and vanished, leaving no trace. Except for his resemblance to a man suspected of a homicide involving a nerve agent. The only clue is the mysterious death of an odd blue-eyed primate Keith brought back from East Africa. Rick and Laura's search takes them to an uncharted island off the coast of Mozambique and into the hands of unscrupulous game smugglers, and toward the edge of evolution.