The story of Assault at Selonia picks up where the first book, Ambush at Corellia, left off. The New Republic is struggling to maintain its power, and the tensions between the government and the Corellian system are escalating. Han Solo and his family are caught in the middle of the conflict, as they are natives of Corellia and have ties to both sides.

As the situation worsens, Han and his wife, Leia Organa Solo, travel to Selonia to investigate a mysterious new threat to the galaxy. There, they discover that an evil mastermind is behind a plot to destroy the New Republic and restore the Empire's power. The Solos must work quickly to uncover the truth and stop the villain before it's too late.