The Robinsons, Earth's first family of outer space, head to colonize Alpha Centauri in their flying saucer, the Gemini 12, but crash land on an uncharted planet where they deal with its challenges and dangers.
Date: October 16, 1997. The Jupiter 2 is to launch, but a saboteur wants to destroy it. Unfortunately he is part of the Jupiter 2 crew now Lost In Space.
Macabre aliens -- quite literally talking heads -- need a humanoid brain to replace a worn out computer in their spaceship. They capture Smith, but quickly realize that his brain is unsatisfactory. The aliens release Smith so that he can bring them somebody more suitable: "a small Robinson."
A small, crab-like robot heralds the arrival of a family of colonists from an alien race called the Taurons. John believes that they are peaceful settlers, but Smith insists that they are the vanguard of an invading army.
Will's "message-in-a-bottle" experiments deplete the supply of fuel for the Jupiter 2. John and Don work on an alternate fuel source, but they cannot stabilize the output. Deciding to build a smaller, 2-man craft, they pull the reactor chamber out and use Will's experiments to construct a "space raft."
Banished from camp for his latest endangering behavior, Dr. Smith discovers alien plants that can duplicate things (including people), which he uses to his advantage.
Using a matter transfer device left behind by the Taurons, Will beams himself back to Earth. He arrives safely in the small town of Hatfield Four Corners, Vermont, but his pleas for help are considered the fantasies of a runaway boy.
The Keeper is an alien who travels the galaxy collecting living pairs of interesting or rare animals. His courtly overtures towards the Robinsons belie his true intention -- to add a pair of humans to his incredible menagerie.
Troubles with The Keeper would be over if Dr. Smith hadn't skulked aboard his ship and released all the animals, putting The Keeper in a position to blackmail the Robinsons for their children.
Will becomes fast friends with Captain Alonzo P. Tucker, an Earthling who escaped his alien captors to become a wandering space buccaneer. But Tucker's roguish charm hides a secret that could destroy them all.
After ruining the Robinson's food supply, Doctor Smith makes a deal with the space trader and gives his body for food provided he collects it in 200 years. The space trader comes to collect immediately.