Only ten days after the events in the original G-Police, the sequel G-Police: Weapons of Justice centres around a group of small gangs in Callisto. The various gangs are taking advantage of the G-Police by exploiting their weakened and exhausted task force. With crime back on the rise, the city will have to pull through and pray for a miracle—fortunately, their prayers have been answered. After an attempt to silence the terrorist organisations, your squad receives word of Marines being sent in to help with the current situation. Unfortunately, they're a few days away from the city, and the G-Police can't keep things under control; the rivalry between good and evil heats up before their arrival. Things are already too late when the Marines and their heavy firepower enter the city. Those small gangs have become full-blown crime syndicates, making the force of good's job much harder. Fortunately, your squad of officers has the upper hand. The G-Police uses a variety of five-attack choppers, including the Venom and Havoc. Additionally, the Marines supplied their Corsair cruise ship, Raptor and Rhino: a giant mechanised robot used for mass destruction and a heavily armed patrol vehicle.