The Rossetti Letter by Christi Phillips
The Rossetti Letter by Christi Phillips (2008) skillfully combines the stories of Venetian courtesan Alessandra Rossetti, who broke the Spanish Conspiracy in 1618, and modern-day American graduate student Claire Donovan.
Alessandra and Claire's stories and motivations unfold in alternating pieces as Claire heads to Venice as the chaperone for a teenager, but truly to uncover the story of what happened in 1618 in order to finish her dissertation. Add the pressure of a professor with a book ready to publish saying that Alessandra actually served as a co-conspirator in the plot to take over then-independent Venice.
And the descriptions of Venice--sigh.
My overall personal rating of The Rossetti Letter is a B.