Lincoln Rhyme is back, and on the trail of a killer who is crippling New York City by manipulating the electrical grid, creating arc flashes so searing that steel melts and victims are set afire. As officials fear terrorism is at hand and investigate various organizations, Rhyme and Amelia Sachs race to decode the forensics to prevent the next assault and uncover the killer. Meanwhile, Rhyme consults on another investigation involving the Watchmaker, one of the few criminals to have eluded Rhyme's net.