Drifting through a party celebrating 400 years since the Spanish Armada's successful invasion of Britain, Don Miguel Navarro - Licentiate of the Society of Time - is shaken by the host's possession of a flawless mask from an ancient Aztec festival. 'Imported' from the past, the discovery signals a breach in the Society's policing of time-travel and imminent danger to reality itself. Today, a relic out of time; tomorrow, the rewriting of the course...