The script contained a scene where The Doctor replaces his destroyed sonic screwdriver by simply getting a replacement from a room full of the devices in the TARDIS. John Nathan-Turner vetoed this, as he was insistent about removing it from Doctor Who.
The date that this episode ends is Sunday, September 2, 1666 - the start of the Great London Fire.
This episode was watched by 10.1 million viewers on its original transmission.