In 1942 Paris, architect Lucien Bernard accepts a commission that will bring him a great deal of money—and maybe get him killed. All he has to do is design a secret hiding place for a Jewish man, a space so invisible that even the most determined German officer won't find it while World War II rages on. He sorely needs the money, and outwitting the Nazis who have occupied his beloved city is a challenge he can't resist.

Soon Lucien is hiding more souls and saving lives. But when one of his hideouts fails horribly, and the problem of where to conceal a Jew becomes much more personal, and he can no longer ignore what's at stake.