The cats of "The Book of Night with Moon" find themselves in Victorian England, battling the forces of darkness. When a worldgate in London appears to be malfunctioning, Rhiow and her team are sent to investigate. They find that the gate is whiplashing through time, with disastrous consequences.
Used availability for Diane Duane's On Her Majesty's Wizardly Service
July 1998 : UK Hardback
December 1998 : UK Paperback