To stop an unseen enemy from destroying the Campus, Jack Ryan Jr. is led to the South China Sea where he, after a midair collision serves as a flash point, must put the pieces of a conspiracy together to stop the world's two remaining super powers from going to war.

"When the leader of North Korea is catastrophically injured, his incapacitation inadvertently triggers a "dead-man's switch," activating an army of sleeper agents in South Korea and precipitating a struggle for succession. Jack Ryan, Jr. is in Seoul to interview a potential addition to the Campus. But his benign trip takes a deadly turn when a wave of violence perpetrated by North Korean operatives grips South Korea's capital. A mysterious voice from...