London: September 2008 Leo Harrison is investigating the murder of a woman washed up on the banks of the Thames. She has been raped, mutilated and a symbol carved onto her chest. Unable to trace the symbol, the police call on the expert knowledge of Helena Carey, historian and occult specialist. She recognises the symbol as being the mark of serial killer Alexei Vorontsevich, executed for similar crimes in 1796. They soon discover that the victim is the killer's third, and that all the female victims share the same rare genetic condition; but the connection to Vorontsevich remains elusive. When a fourth woman with the condition goes missing, Leo and his colleagues must find and save her from a manipulative, predatory killer. Working together, Leo and Helena's professional chemistry turns into personal happiness. Their passionate affair becomes a refuge from the brutal world that brought them together. But their happiness is short lived - death surrounds Helena; the past won't stay buried and the shadow of the murders never seems to be far from her door. When Helena is forced into revealing a dark secret, heartbroken Leo is left questioning everything he believes in. As past and present collide, those standing in its wake will have to fight to survive.