This was Uma Thurman's first acting job, although because of the inordinate production delays for this movie, was not her debut. She also belongs to the very short list of actors who were hired on their very first audition.
A moon city set was to have been built at Pinewood. However, since there was no money left to do this, Terry Gilliam took the sketches of the designs, and stuck them to a board. The 2D buildings were then moved forwards/backwards and left/right. The result is bizarre and effective.
Robin Williams was cast last-minute, after the budget had run out. His role is uncredited and unpaid.
Forms an informal trilogy with director Terry Gilliam's previous films, Time Bandits (1981) and Brazil (1985). The three movies represent the three stages of Man (youth, middle age, and elderly) and the impact of imagination on each. Jack Purvis and Winston Dennis appear in all three films. Of the three, this is the only one is which Dennis has speaking lines and his face is seen.
John Neville was not a film actor at the time, preferring the theater. However, he was also a big Monty Python fan so he readily agreed to take the lead.
Terry Gilliam: as "irritating singer inside fish". He originally filmed an additional scene where he sat against the wall of the ship, coughing, and died almost immediately, in exactly the same manner as his cameo as the animator in Monty Python and the Holy Grail (1975).
Terry Gilliam: [persons of short stature] in most every Gilliam film there is an actor of short stature. In this one, the character of Gustavus is played by Jack Purvis.
Terry Gilliam: [cages] On the Moon, the Baron, Sally and Berthold are imprisoned in a style of cage seen often in Gilliam films.