Just trying for a relaxing vacation, Dr. Grace Farrington discovers what might be missing evolutionary DNA from a fisherman's net on the island country of São Tomé and Principe. Later. in a rustic beach cabin with Kurt. their overdue romantic interlude is interrupted with the news that her best friend, Freya, has been arrested for murdering a man in Senator Kincaid's boathouse. Cutting her vacation short, Grace returns to New England and Oyster River Research, where Freya isn't talking. Unfortunately the Kincaid's mysterious "caretaker" was murdered with the same tenth century trimming ax that Freya uses to build her Viking ship reconstructions. Furthermore, although Freya is trying to hide it, this dangerous, blackmailing deadman may have been her son Mac's real father! But even while Grace investigates to prove her friend innocent, she's drawn into another complicated genetic code mystery, this one involving the last Czar of Russia and his missing daughter, Grand Duchess Anastasia.