Bestselling author John Macken takes the forensic thriller into unchartered genetic territory in this gripping thriller. Fans of Kathy Reichs, Karin Slaughter and Patricia Cornwell won't be disappointed.'Macken speaks with authority about the science and knows how to put a tense and absorbing story together' - OBSERVER'You always get something different from John... he takes it to a new extreme' -- ***** Reader review'A cracking story... it is eminently readable' -- ***** Reader review'A very intelligent book' -- ***** Reader review********************************************************PUSHED TOO FAR, EVERYONE BREAKS...There is a killer loose on the London Underground. He kills without leaving any forensic trace, and seemingly without motive. Genecrime, the UK's elite forensic unit, are stretched to the limits trying to find one usable clue.And there is another problem facing Genecrime. Before he was sacked as head of the unit, Reuben Maitland developed a system to predict latent homicidal behaviour from people's DNA. Now rogue elements in the police, believing that prevention is better than cure, are using Reuben's research to hunt down and incite latent psychopaths beyond their breaking point.Reuben must track down whoever is misusing his technology and stop them before more lives are destroyed. But what he cannot know is that his investigation will lead him directly into the path of the Underground killer...