Quite simply, one of the best storytellers around Tess Gerritsen

Called out to examine the body of a female construction worker at a Cleveland building site, forensic scientist Theresa MacLean soon discovers that what she initially assumed to be an industrial accident may be nothing of the kind. For why was the dead woman smartly dressed? And what would she be doing on the 23rd storey of an unfinished building in the middle of the night?

Then it turns out there was a witness to the death: a young girl nicknamed Ghost due to her habit of slipping silently and watchfully around the neighbourhood. Ghost saw the woman fall. Except Ghost says she didn't fall - she was pushed by someone Ghost can only identify as the Shadow Man.

Soon Theresa finds herself in a race against time to protect Ghost from an unknown killer before he is able to find the little girl and silence her for good.