Sancia Grado is a scarred, hardened thief who survives in Tevanne, an industrial city ruled by four rival merchant houses and powered by scriving—the magical art of convincing objects to disobey the laws of physics. Hired for what looks like a simple job, she breaks into a heavily guarded warehouse and steals a small case, only to find it holds Clef, a sentient and talkative magical key unlike anything she has ever encountered. The theft draws the attention of Captain Gregor Dandolo, the closest thing Tevanne has to real law enforcement, and pulls Sancia into an investigation alongside the eccentric master scriver Orso Ignacio and his assistant Berenice. As the powerful House Candiano moves to reclaim Clef at any cost, Sancia begins to uncover a forgotten, far more sophisticated form of scriving buried in the city's past—one that could remake Tevanne, and the world beyond it, for good or ill. Foundryside is the first novel in Robert Jackson Bennett's Founders trilogy.