DNA

Robert Gibson's murder looks almost exactly like the crime scene from a case that drove Joe Donovan into a breakdown and early retirement seven years earlier. One detail stands out, however: the name "Donovan" printed on a wall in the dead man's blood, which he interprets as a personal challenge.

With Gibson's murder still unsolved, another body turns up murdered in nearly identical fashion--that of Philip White, a colleague and lover of Kate Donovan. Could the cuckolded scientist have killed White out of jealousy in a fugue state? Or is the murderer another member of the Donovan family?

Now back as senior scientist in the Forensic Investigations Unit, Donovan doggedly pursues a serial killer who takes pretty blonde women as his victims. He thinks he knows not only the killer, but also the next target--Sharon Page, a pub owner looking for more from Donovan than merely protection.

When wealthy Stephen Parker is found shot through the chin in his swanky home, it seems like a robbery gone wrong. The evidence points to John Pinion, a self-proclaimed "investment advisor" to whom Parker owed ₤8,000. But Donovan suspects the victim's son, who seems unnaturally close to his mother.

The entire FIU team rushes to a secluded air force base, where a cargo plane has landed with all of its passengers and crew stricken by an unknown illness. Authorities believe it's biological terrorism. But Donovan focuses his attention on the plane's mysterious human cargo--an unnamed, blindfolded prisoner.