Florence 1538

Artist Benvenuto Cellini creates the Medusa Amulet: a work of unimaginable power - and menace. The amulet can grant immortality to any who stare into it on a moonlit night, but it soon falls into the wrong hands.

Chicago, the present day

Art historian David Franco's beloved sister Sarah is dying. When a mysterious widow offers him a million dollars to find the legendary amulet, David seizes the chance to pay off Sarah's medical bills - and offer her a chance of survival.

The result is a desperate race against time that will take him across centuries and continents, from American archives to Renaissance courts, from the ramparts of the French Revolution to the dark depths of the Nazi party.

And there are others who have heard of the amulet's powers and they will stop at nothing to find it...