Michael Kilgarriff nearly turned down this project because he discovered that he wouldn't be speaking the Cyber Controller's dialogue, as well as appearing on screen. He, of course, relented and indeed did play the on-screen presence of the controller while the voice was provided by voice actor Peter Hawkins.
This episode takes place on Telos in the 25th Century.
The first ever story to feature The Cyber Controller.
Based on the Previous Cyberman Story which was set in 2070 and dialogue in this story stating that the cybermen died out 500 years prior the date of this story is 2570 or a nearby year.
This episode was watched by 6.4 million viewers on its original transmission.