In the spring of 1523, Cardinal Wolsey's "beloved" nephew, Benjamin Daunbey, and the latter's rapscallion servant, Roger Shallot, are summoned to London. A Florentine envoy, Lord Francesco Abrizzi, has been foully murdered in Cheapside. He has been shot in the head by a new-fangled hand cannon and King Henry VIII, the "Great Beast" of Shallot's memoirs, is determined to unmask the perpetrators of this outrage. In London, Shallot experiences King Henry VIII's rage and spite, the insults of the Abrizzis, and a murderous attack on his own life. Shallot, a born coward with the fastest legs in Christendom, just wants to crawl away and hide, but Henry VIII and Wolsey are most insistent: Shallot and Benjamin are to journey to Florence, discover the identity of Lord Francesco's assassin, deliver a secret message to Cardinal Guilo de Medici, Prince of the Church and ruler of Florence, as well as inveigle back to England a Florentine painter. It sounds simple enough - but the reality is murderously different: they experience murder onboard ship, pursuit by Turkish corsairs, the Satanic rites of a black magician, and bloodshed on every side.