Libertus must solve a mystery when the guest of honour is found dead in the vomitorium.

Present at a banquet where the guest of honour is found dead, Libertus is horrified when his patron, Marcus Septimus, is arrested on suspicion of murder. Libertus starts to investigate but when he is accused of being an accomplice in the murder he is forced to go on the run. Soon his life is in danger and there's no one to help.