Apprentices Jasper and Maeve discover a critical substitution crisis in the Toy Repository. Cheap, resonance-absorbing red ribbon has been swapped for the necessary acoustically dampening silver twine on a shipment of clockwork toys. Jasper realizes this sabotage links to the larger subterranean disturbances felt elsewhere, as the faulty ribbon will cause the toys to fail under ground cold. To counteract the structural degradation and potentially counter the sabotage, Jasper decides they must illegally access the sealed Historical Chime Maintenance Access tunnel to retrieve emergency backup resonators, which are designed to stabilize the Great Clock Tower's chime against foundation shifts. They successfully breach the seal, finding the space filled with the scent of ozone and warm brass, and hear a high-pitched whine emanating from the resonators, suggesting the sabotage is indeed tied to the town's central timing mechanisms.