During his investigations Aldo uncovers a plot to overthrow the volatile ruler of Florence, Alessandro de’ Medici. If the Duke falls, it will endanger the whole city. But a rival officer of the court is determined to expose details about Aldo’s private life that could lead to his ruin. Can Aldo stop the conspiracy before anyone else dies, or will his own secrets destroy him first?

When Cesare Aldo investigates a report of intruders at a convent in the Renaissance city’s northern quarter, he enters a community divided by bitter rivalries and harbouring dark secrets.

Cesare Aldo was once an officer for the city’s most feared criminal court. Following a period of exile, he is back – but demoted to night patrol, when only the drunk and the dangerous roam the streets.

A night patrol finds a wealthy merchant hanged and set ablaze in the city’s main square. More than mere murder, this killing is intended to put the fear of God into Florence. Forty years earlier, puritanical monk Girolamo Savonarola was executed the same way. Does this new killing mean his fanatical disciples are reviving the monk’s regime of holy terror?