After the Stranger has rescued Atrus, the master of "linking books", from the imprisonment caused by his sons, a new task awaits the hero. Atrus's wife, Catherine, has been taken by Gehn, his own father. Gehn has appointed himself as the one to rule the Age of Riven, and has driven his world to collapse. Now he holds Catherine hostage on Riven, hoping that his son will restore the book link to the Age and free him from there. The Stranger is requested by Atrus to travel to Riven and find a way to rescue Catherine.