Jack Ryan has protected the United States from enemies foreign and domestic, but this time the whole planet may be at risk in the latest entry in Tom Clancy's #1 New York Times bestselling series. The Russians say that the mysterious explosion in a Siberian "chemical plant" is just a local concern. If that's the case, why have they cordoned off hundreds of square miles, and why are there reports of local people dying of a mysterious illness? It may be the Russians' fault, but it's the whole world's problem. U.S. President Jack Ryan needs answers if he's going to stop the spread of this virulent contagion. But time is running out--and this time, even Jack Ryan might not have the answers.