The story begins in August 1643. The Civil War in England is a year old, but has yet to touch the life of Thomas Hill, a mathematician and bookseller in Romsey on the south coast. Thomas lives quietly with his books, his widowed sister and her two children. This changes quickly when Thomas is bullied by a party of royalist Dragoons passing through the town, and then is unable to prevent his shop being ransacked by parliamentarian troops a few days later.

The war encroaches even further when Thomas is summoned to Oxford by his old tutor Abraham Fletcher, who has recommended him to the King as a suitable cryptographer. He is escorted in secrecy to Oxford by Simon de Pointz, a Franciscan friar, who prepares him for the many changes to his old home, which has gone from a genteel university town to a rough-and-ready garrison.

The King's fixer Tobias Rush arranges for Thomas to be given a room in Merton College, where he immediately finds an enemy in the form of Francis Rayne, a royalist captain more interested in drinking and whoring than fighting for the king, and soon also finds a girlfriend in Jane Romilly, one of the Queen's ladies in waiting.

Thomas is an interesting character. As a pacifist with no real leaning towards either side in the war, he initially agrees to help the royalist cause for largely impersonal reasons - bringing an early end to the war - but as events progress, matters become more and more personal.

Equally interesting is the Queen's confessor, the Franciscan Friar Simon. From his first encounter with Thomas onwards, he displays a strange skill-set for a man of the cloth, all explained away by a boisterous boyhood on the streets of Norwich.

Hill's first real taste of war - the Battle of Newbury - is painstakingly described (and I'm sure has attracted the close attention of military history buffs). But for me, two features made the 17th century live. The first is that the author is not afraid to describe the unsanitary world his characters inhabit: "The crush of bodies around the stall forced him into the middle of the street, down which ran a reeking open drain, half blocked in places with shit and refuse".

The second is the meals. Hill is treated to a number of delicacies I'd like to sample, including shaggy inkcaps roasted on a campfire, eel and oyster pie, roast mutton with oysters and radishes, sweet apple cream flavoured with ginger and lemon.

A good deal of the book concerns Thomas's attempts to decipher secret messages passed between Parliamentarians. These increase in difficulty as the book progresses, but the author does a good job of making the process of decryption engaging and I actually gave a little internal cheer when he worked out the number of letters in a key word. I must admit that following the process closely would require more serious thinking time (for this reader at least) as he covers key words, double and triple alphabetic ciphers, homophonic ciphers, numerical substitutions, nulls, nomenclators and Vigenère ciphers.

This is the first of a trilogy featuring Hill. The author has thrown a lot at this book: battles and brawls, intrigue, romance and revenge, code-breaking. I hope he can keep up the pace in the next two installments.

NB: This was first published in 2010 as THE KING'S CODEBREAKER.

Rich Westwood, England
September 2012