The Courtesan's Secret — Nina Wachsman

When an envoy from the New World comes to Venice, the elite courtesan Belladonna fears the secret of her origins may be revealed. The Spanish are after him, for he carries the map to a great treasure. When the envoy disappears, his enemies shift their pursuit to Belladonna, their only key to his whereabouts.

To avoid capture by the Spanish, Belladonna must abandon her luxurious palazzo, and take refuge in the Ghetto with her friend, Diana, the rabbi's daughter. Hiding in plain sight behind the Ghetto walls, she must find the envoy and confront her past. Faced with terrible choices and an uncertain future, Belladonna must decide whether to sacrifice all she has achieved for a love she has always desired.