ShadowStrike poisoned the water of Trinity Falls two months ago. Now the Trinity Four, the teens most affected by the poison, have been isolated in a remote mansion under twenty-four-hour medical care while scientists on four continents rush to discover a cure. Meanwhile, U.S. operatives scour the world for the bioterrorists responsible for this heinous crime, as two teen virtual spies, also infected, hunt for the criminals on the Internet. The danger remains real - for ShadowStrike has every reason to pursue the Trinity Four, and their evil plan will unleash a new designer virus that's even deadlier than the first.