When brilliant, driven and idealistic scientist Jeffrey Horton discovers the Trigger effect, he knows at once that he's changed the world. He is in possession of the ultimate weapon: a device that can disarm an enemy's entire arsenal, from rifle bullets to nuclear warheads. But the Trigger is not just a weapon. It can be used to end for ever the power of the gun. Except that, in a world in which violence is epidemic, anyone proposing an end to the use of weapons is a target for killers.