Luke Skywalker is alarmed. Several Jedi Knights (including his nephews, Solo and Jacen Solo) disappeared into the Unknown Regions after answering a call for help that only they could hear. The isolationist Chiss have filed a formal complaint, accusing the missing Jedi of interfering in a border dispute between the Chiss and an unknown aggressor. Luke has no choice but to fly to the Unknown Regions and attempt to defuse the rising tensions before they erupt into open conflict. Han and Leia go there, determined to protect their children from possible mortal danger. But none of them is prepared for what they discover upon arrival. A colony of mysterious aliens is expanding, approaching the borders of Chiss space. The leader of a swarm of strangers is determined. An adept of the Force himself, he calls old friends to his side, convincing them to join the colony and unite the Force. Even if this leads to total war...