A bombing in London kills fourteen people. Detective Inspector Ashley Bertoni survives but faces early retirement. His forensic officer, Cally Boyce, loses everything in the explosion - her partner and only love, Tyler, her best friend, Galen and her memory. Cally saw the bomber, but global amnesia prevents her from remembering anything leading up to, or since, the explosion. Special Branch suspect animal rights activists of the attack, but Bertoni is convinced it is connected to experiments Tyler had been conducting into the recurrence of identical DNA. This evidence could reveal a secret shrouded by a vow of silence and buried since the beginning of time. To escape the nightmare, Cally knows that the vow of silence has to be broken and retribution must follow. It is the oldest secret in the world...and the world is about to find out.