Political intrigue in Rome set against the background of the blood purges of the 5th century AD. Marcus's wife is caught up in the urban prefect's net as accessory to so-called treason. Another exciting Marcus Gregorianus Numidianus novel. The author states in the Historical Note that this whole series has been based on the writings of Ammianus Marcellinus, the contemporary historian of that era. The title refers to a special rope and box in which people are encouraged to accuse others of crime. ( )