An atmospheric, intricately plotted new mystery in which Sherlock Holmes and Henry Vernier race to catch a villainous murderer at large in the Vatican and Rome. Sherlock Holmes and his cousin, Henry Vernier, are holidaying in Italy when Holmes is summoned by the Pope for a private audience - the Holy See asks the world's greatest detective to find the stolen forefinger of Saint Thomas.
When the relic is quickly and mysteriously returned, all seems to be resolved. But events are turned upside down as the relic is stolen again, and a guard brutally murdered.
With fresh blood spilled, Holmes and Vernier must follow the trail of a sacrilegious murderer through the streets of Rome, the halls of the Vatican, and beyond.