Not even settled into marriage yet, Arianna and her husband find themselves en route to Edinburgh with Basil Henning. In their last adventure, they learned more about a traitor named the Fox. This person has escaped all attempts at exposure and has ruthless killers working for him. On their way to London, the three are beset by a trio of idiots. Leaving their bodies behind, they complete the trip to Edinburgh. Sandro and Basil set out to reconnect with Basil's old schoolmates, leaving Arianna to seek out information in the market.

What they learn will send them back to London with news of a disaster that could hand Bonaparte the means to defeat England. Basil was shot shortly after their disocvery of Girton's body; further complicating the situation.

Arianna goes undercover at the Royal Institution, as society devoted to chemistry and organized by Humphery Davy. Sandro and Basil investigate the mysterious disappearance of another chemist.

As they come closer to exposing the organization, other secrets will be exposed. Sandro must introduce Arianna to one of his closest friends, Miss Sophia Kirtland. Given that Sandra married Arianna in a rather hasty fashion, she has always been rather jealous of Sophia's relationship with Sandro. Sophia will be needed to introduce Arianna to the Royal Institute since Basil is recovering from his wound.

Truly a delight to read, RECIPE FOR TREASON, the third book featuring these characters combines historical fact with a fictitious villain and excellent conjecture. Chocoholics will love the book for the recipes alone. Historical mystery lovers will be enthralled by the politics of the early nineteenth century. Regency readers won't want to miss the deepening of the relationship between Sandro and Arianna.