For readers outside the United States and (I think) Canada, Head of Zeus has been offering special Christmas deals on its books and today, The Seventeenth Day of HoZmas, the book is Four for A Boy

DEATH IN BYZANTIUM: At the heart of what is left of the Roman Empire, lies a city simmering with intrigue & treachery. Amid this maelstrom stands John, a slave who has risen to become the right hand of Justinian, the greatest of Byzantium's emperors. With violence and murder commonplace, it is John's skills as an investigator that the Emperor prizes the most.

In this series prequel, John the Eunuch takes his first dangerous steps along the path that will lead him to hold office as Lord Chamberlain.

In the unnaturally cold winter of 525, the city is convulsed by doubt and riots, Emperor Justin is dying and the streets are terrorized alternately by a group of thugs and forces under the City Prefect. When a wealthy philanthropist is murdered, rumours abound that the heir to the throne, Justinian, is trying to sway the succession. In an attempt to clear his name, Justinian engages an anonymous slave called John to investigate what many believe could be part of a succession conspiracy.

To discover for £1, click here.