Christie’s official biography states that the play was written after she and her husband, Max Mallowan, returned from their annual summer season at the archaeological dig at Nimrud in 1952. The producer of the play, Ayton Whitaker, found the script to be "first rate" saying that it made, "full use of radio techniques and possibilities." It appears that Christie either did not specify Newton Abbot as one of the locales in the play or was happy for it to be changed, saying, "Any station will do. Newton Abbot telephone boxes and station geography would have to be vetted, of course."