Robert Emhardt, playing Professor Rankin, states that he is 51, but, in spite of how old he really looks, the actor was only 42 at the time.
The title is a shortened version of the Latin phrase "de mortuis nil nisi bonum dicendum est" or "Speak no ill of the dead".
A number of John Collier's (writer of this episode) short stories were adapted in both this series, and Roald Dahl's Tales of the Unexpected.
Robert Emhardt and Henry Jones starred together in the classic western, "The 3:10 to Yuma".