The city has surrendered to a wave of heat in the July 1956. When detective Mike Reardon is on the way to work for nightshift he is shot to death from behind with a 45 caliber handgun. As Steve Carella and his colleagues from the 87th Precinct are looking for their friend’s killer, none has any idea that it is just the beginning of a series of police murders. David Foster is the next victim at the entrance of his apartment. The killer has left behind a footprint at the crime scene. Steve Carella and Hank Bush question some suspects,but to no avail.. A few nights later the unknown killer ambushes and murders Hank Bush,but at the cost of his getting wounded. Steve Carella will be the next target if he fails to stop him.