Philip Benedict's Season of conspiracy opens like a detective novel. A police detail interrogates Pierre Menard, a Lyonnais cabinetmaker, about his role in the abortive conspiracy to seize control of Lyon during the tumultuous events of 4–5 September 1560. Faced with torture, ‘Menard’ admits his involvement in smuggling weapons and soldiers into the city and hiding them. He confesses that his real name is Gilles Triou, and that he entered Lyon from Geneva. Thus begins Benedict's painstakingly detailed research connecting the Conspiracy of Amboise (9 March 1560), the Lyon ‘Maligny affair’ of 4–5 September and members of the nobility and French Reformed Church in further conspiring that continued well into October. Their intent was to compel Antoine of Navarre to accept Huguenot military assistance for a rising to force the calling of the estates-general which, it was hoped, would eliminate the Guise regency and endorse Antoine's influence over the young Francis ii. As an important by-product, the estates would call for a reformation of religion in France and the elimination of the Guise family from power. Catherine of Guise, Duke Francis, the Cardinal of Lorraine and other members of the family were instrumental in persecuting the fast-growing French Protestant movement. But on 30 October, to the consternation of the plotters, indecisive Antoine and his Protestant brother Louis de Condé meekly entered Orleans and submitted to the crown. Benedict concludes that the magnitude of the conspiracy startled the royals and brought even greater repression onto the Protestant movement.

Benedict first reviews the historiography of the three events, creating yet a second detective chronicle every bit as fascinating as the first. ‘Historians’, he notes, ‘repeat one another’. Protestant apologists, writing just after Amboise, blamed adventurers in the nobility for the conspiracy and downplayed the role of the Reformed Church and especially of John Calvin. This narrative was repeated intact by most French historians over the succeeding centuries. But was that accurate? Like all investigators, Benedict asks, ‘Who knew what, and when did they know it?’ Many French records were purposely destroyed after the death of Francis ii. In late 1800s the Genevan council registers, city legal proceedings, consistorial records and registers of the Company of Pastors all began to be transcribed, catalogued and printed. Calvin's and Beza's correspondence also became available, allowing their letters to be linked with people and events. Incriminating links between many of the City's French pastors and habitants in the Amboise conspiracy and the Maligny affair quickly emerged. In fact, two Genevan historians, Henry Naef (1922) and Alain Dufour (1963), and Robert Kingdon (1956) all noted Calvin's likely involvement in the plotting by cross-referencing these sources.

But Benedict advances this linkage many steps further, benefitting from access to additional source material from France, England and Switzerland. He tracks some of the major conspirators back to Geneva; in fact, two even lived on the same street as Calvin. Others were French émigré friends. The Reformer is discovered to have contributed his entire savings to the venture. As much as the Genevan Church and councils sought to retain ‘plausible deniability’ of involvement in the plot for fear of angering the French crown, it is improbable they were innocent. Fifteen participants at Amboise appear in the Genevan Livre des habitants and resided in the city, and between seventy and 400 Genevans participated in the event.

The plot was destined to fail. It was so widely discussed, both in correspondence and face-to-face meetings across Europe, that it was uncovered by those loyal to the monarchy a full three weeks before it would have been executed. Benedict also uncovered a fascinating link between Amboise and Queen Elizabeth. Correspondence implicated her government and Scotland's ‘Lords of the Congregation’ with the plotters. They had a common enemy: the Guise family. Mary Queen of Scots (the young wife of Francis ii) and her mother Mary of Guise sought to control political and religious events in Scotland as a stepping-stone toward dethroning Elizabeth and allowing Mary to reign in both countries.

This book is a masterful example of original source historical research. Benedict connects people and events in a web of conspiracy that propelled them all into the French Wars of Religion. It is well-written, and the conclusion cogently argued. It does require a solid knowledge of the era, for Benedict devotes little space to introducing the reader to the broader picture. It does, however, fill in over the course of the book, and a second reading is much more illuminating. For any student of this era, Philip Benedict has performed an invaluable service and advanced his reputation as one of the great scholars of this period.