Following the wish of his grandfather, the mysteries of David's past begins to open up before him. The map leads him into the heart of the dangerous Basque mountains, where a genetic curse lies buried and a frightening secret about the Western world's past is hidden.
Amy, a friend of Garovillo, who happens to be Miguel’s father, arranges a meeting, where Garovillo informs David that David’s grandfather was a Basque. He advises David to forget about the map. But before he can reveal more, Miguel arrives and chases David and Amy all around Basque Country and beyond, as they ignore the old man’s advice and follow the map instead.
Meanwhile, Simon Quinn, a London-based freelance journalist, covers a series of murders that seem to have something to do with the Cagots, a long-persecuted and nearly extinct ethnic minority from Basque Country. His investigation puts him in contact with David and Amy, and together, facing danger at every turn, they must uncover a centuries-old and well-protected secret, the exposure of which could really ruin things for racial and ethnic harmony worldwide.
Shifting from the forgotten churches of the Pyrenees to the arid deserts of Namibia, Knox weaves an astonishing tale based on ancient scripture, medieval history and contemporary science to create, identify and exploit potential and speculative human speciation in his second religio-political thriller, The Marks of Cain.
Knox excels at meticulous research - some passages are quite fascinating although gruesome - but this effort doesn't really translate fully into a coherent and credible thriller. The final result is a compelling story on genetic experiments on racial profiling started by Nazi scientists during Hilter's time that finally catch up to the present day. Still an interesting book for those interested in religious thrillers.