Vis works in the Catenan prisons in Letens. One evening, a stranger arrives to interrogate a prisoner. He has official permission from the Senate. Vis unhooks the prisoner from a Sapper, an ancient technology from a dead civilization that drains a person’s Will to be used by the Catenan elite. The stranger questions the prisoner in a dead language that Vis should not understand but does, catching snippets including the words Obiteum and Luceum. The prisoner struggles and knocks Vis into the Sapper, which should harm him but does not. The stranger pretends not to notice.

Vis lives in an orphanage, working at the prison during the day and fighting in an underground fighting ring at night. That night, the owner of the ring tells him he will be fighting a Sextus (Sixth). Catenan hierarchy is built on ranks from Octavii (Eighth) to Princeps (First), underpinned by how much Will they receive from others. Each level offers increased levels of physical strength, mental skill, and the ability to use Will as magic. Vis, who refuses to either receive or cede Will, has never fought a Sextus before and will likely be severely injured.