The romance of Casablanca meets the spy world of Ian Fleming in this WWII love story for the ages.

In a glittering city of secrets and shadows, love is the most perilous gamble of all.

Lisbon 1943. As two American librarians are drawn into a city of dangerous subterfuge and unexpected love affairs, they are forced to choose between their missions and the men they love. Brimming with evocative writing and meticulous research, award-winning author Suzanne Nelson spins a web of secret aliases, sweeping romance, and great sacrifice. Inspired by real historical figures, this is the captivating story of two remarkable young women, their bravery and heartache, and a friendship that withstands the ravages of war.

With World War II raging across Europe, best friends Selene Delmont and Beatrice Sullivan are enlisted by the US Intelligence Office and sent to Lisbon-a sparkling city and hotbed of trouble, harboring exiled royalty, hunted refugees, and spies trading double-edged secrets in seductively dark corners. In official capacity, librarians Selene and Bea have been recruited to catalog the vast mountain of information gathered by the Allies, but by night, both women are undercover agents tasked with infiltrating the Axis spy network.

Where Selene is confident and brash, Bea is bookish and careful. Selene longs to escape her family's impossible expectations and embrace her independence, while all Bea wants is to heal from heartbreak and keep impulsive Selene out of trouble. But soon, both librarians are caught up in treacherous games of deception alongside two of Lisbon's most notorious men-the outcast Portuguese baron, Luca Caldeira, and the lethal double agent, Gable. As Selene charms her way through lavish ballrooms and fêtes with Luca, Bea is plunged into Gable's shadowy underworld of informants.

Victory depends upon the joint success of their missions, but when an unexpected betrayal throws a carefully spun web of lies into chaos, everything they've sacrificed is put at risk. As Selene and Bea are pushed to their breaking points can their friendship, and their hearts, survive the cost of war?