John Bennett played the Greek Physician to Derek Jacobi's Emperor Claudius in the series I, Claudius (1976) - a reversal of sorts of their roles in this program. Similarly, Norman Eshley who plays a victim in this performance, is one of the conspirators to murder in the same episode of I, Claudius (1976) - the episode being Fool's Luck (1976).
This episode is based on the fifth novel in "The Cadfael Chronicles", which was published in 1981.
This is the first episode to feature Cadfael in the opening scene.
At approximately 23:38, the actor playing the murdered man clearly breathes.