Juusei to Diamond

Onizuka Youichi - the negotiator from New York - has contracted with the Japanese police and is working for Zero Department, which had been newly formed to specialize in hostage negotiation.

However, when another department request investigation of stalker case due to being short-staffed, Onizuka is unaware that it is sign of series of dangerous events soon to follow, where he and his co-workers must struggle hard to keep everyone alive, even that of the criminal.