Dozens of shop owners located on the territory of the 87th police station are receiving death threats over the phone. Just jokes or is there something else behind this? The naked body of an old man shot with a shotgun is found. Detective Carella receives a pellet charge in the shoulder and understands the reason for the mysterious calls, but, being unconscious, cannot warn his colleagues. But what is about to happen will exceed any expectations... A murder in a liquor store puts the detectives of the 87th precinct in a big dead end. There are plenty of suspects, but everyone has an alibi. The only lead to the killer is a letter that neither the criminal nor the police can find yet...