Dark secrets lie in the tunnels beneath...

Paris, 1298. Disguised as an outlaw, a personage of the highest rank sneaks through the cellars of Notre Dame. The maze of secret tunnels hides a laboratory. Here, occult studies are conducted under the guidance of the renowned scientist, Arnaldo da Villanova. Studies which remain a secret.

Rome, 1301. Denounced for impiety by mysterious informers in Paris, Villanova seeks refuge in Italy and becomes Pope Boniface VIII's personal physician. Yet Villanova knows a secret, one capable of discrediting and overthrowing the French monarchy. He's not safe. It's clear someone wants to silence him forever.

Will he pay the price for the secret he keeps with his life?

Praise for Barbara Frale:

'An academic who has dedicated years of work to books on this topic ... A pleasure to read' UMBERTO ECO.

'A long-awaited historical thriller' THE REPUBLIC.

'A brilliant writer' IL GIORNALE.