In the original script, Victoria was to have killed Oak (originally named Swan) with her screams.
A subplot was removed from the script in which the Weed attack a conference, as it could now traverse the entirety of Great Britain's network of natural gas pipelines.
Clips survive due to cuts made by the Australian censor.
This episode was wiped by the BBC and no copy of it is known to exist.
It was planned to film scenes with an actual flying helicopter. The idea had to be scrapped during the production after it was discovered that in the night before filming, the pilot went to a pub, where he got heavily drunk, caused property damage and even ate glass. Because of that, Patrick Troughton refused to take off with the pilot. To simulate the flying effect, the director was forced to wheel the cameraman around the helicopter with a pram.