Written by Robert Banks Stewart as a six-part story, the story was commissioned in May 1976. This story was replaced by "The Talons of Weng-Chiang", which used the same basic premise of a villain traveling back in time, when Stewart took up the post of script editor on the series "Armchair Thriller" and was unable to deliver the scripts, forcing Robert Holmes to step in to rework the story. It was later adapted by John Dorney for Big Finish's "The Lost Stories" range in January 2012.