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.