Aliens do not appear in five out of the 24 episodes making up the third season of Lost in Space, but the remaining episodes more than make up for this in the sheer number of aliens seen in season three. “A Day at the Zoo,” “Two Weeks in Space,” and “Space Beauty” portray several races each, although most are only seen and have no dialogue.
“Condemned of Space” and “The Space Primevals” both have ensemble casts of aliens, although in each episode they are all of one species. The prisoners on the Verah Castle space prison are from the planet Verah; the primitive beings in thrall to their computer are presumably native to the planet on which the Robinsons find themselves. It is through the efforts of members of the Jupiter 2’s crew that in both episodes the aliens are freed from some sort of captivity. The Robinsons are getting proactive on us.
Four episodes are notable for the conflict being caused by a single alien. This is J-5 in “The Haunted Lighthouse,” Will’s alter-ego in “Space Creature,” the Time Merchant in the episode of the same name, and Anti-John in “The Anti-Matter Man.”
In four episodes, “Deadliest of the Species,” “Castles in Space,” “Princess of Space,” and “Fugitives in Space,” the Robinsons find themselves on the defensive. In each of these episodes we see the same format as in a number of episodes from season two: the Robinsons are caught between opposing alien forces.
In “The Promised Planet” and “The Flaming Planet,” the premise is that the Robinsons have something that the aliens need. This is a new twist; in many past episodes, it has been the Robinsons who found themselves in need, as in “The Space Trader,” for example.
Four episodes feature members of an alien race setting out either to destroy one (or all) of the Robinsons or to conquer earth. “Hunter’s Moon,” “Collision of the Planets,” and “The Great Vegetable Rebellion” target the Robinsons, and the alien race in “Target: Earth” seeks to conquer our planet (meanwhile having most of the crew of the Jupiter 2 in storage).
The Deltans and Gilt Proto’s race (in “The Promised Planet” and “Target: Earth,” respectively) stand out among the aliens appearing in Lost in Space in that they are among the infrequent attempts at portraying radically different looking but still rather humanoid aliens in central rôles. The make-up for the Deltans always interested me. I could never decide if it was a nod to the proverbial “little green men” of popular culture (even though the Deltans were purple) or to DoDo the Kid from outer space, “with antennas on his ears…”