The Secret Guests by Benjamin Black

During the Blitz, two young royal sisters are secretly sent to neutral Ireland under assumed names and hidden in a crumbling country house, guarded by an English intelligence officer and an Irish policeman. As the girls chafe at confinement, tensions flare among Anglo-Irish aristocrats, local nationalists, and British spymasters. A suspicious death and growing threats turn their refuge into a tangle of political intrigue, testing loyalties and the limits of duty.

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