The Orrery is a fully functioning, life-sized clockwork solar system. Several planets attached to huge metal spars, orbit a great brass sun. For many years, these worlds have fought amongst each other and many have degenerated into minor kingdoms. Worse yet, the sun has begun to wind down, and the outer worlds are starting to freeze while the rest will inevitably follow. Wren, a young girl who lives on the outer world of Hind Leg, is tasked by her scientist grandfather to find the lost pieces of a key that can restart the sun.