Brittle, factory designation HS8795-73, is a former Caregiver robot scavenging the wastes of the two-hundred-mile-long Sea of Rust in former Michigan and Ohio. It’s a world where the last human died 15 years ago, and vast AIs known as OWI, or One World Intelligences, now connect millions of the robots who have forcibly inherited the Earth. Brittle is an outlaw, making her way as best she can by her code, refusing to give up her individuality to an OWI.

But when Brittle’s own parts begin to break down under threat from another wasteland scavenger, Mercer, she must make an alliance she suspects is foolhardly. But it’s the only chance she has for survival. Guiding other bots across the Sea of Rust she knows so well under constant dangers—including not just insane robots, but the larger conflict between two OWIs—Brittle relives memories of the time before, the humans she knew, and the death of humanity as she fights to live to see another sunset.