June 1941. An American plane crashes in the west of Ireland.
Its cargo of booze, cigarettes and caviar destined for the US embassy in London includes a piece of secret military hardware of great interest to the Germans.
The device disappears from the wreckage. Paul Duggan, a young Irish military intelligence officer still pining for a beautiful Austrian-Jewish refugee who has moved on to a new life in New York, sets out to find it before the Germans do.
Meanwhile, the United States and the British are pushing neutral Ireland to help protect their Atlantic convoys, which would involve it in the war.
The search and the diplomatic arm-twisting become entwined and take Duggan to the dangerous back streets of Lisbon, the war’s spy centre, where the intelligence games between the Allies and the Nazis can turn deadly.