The Robinson family was supposed to set off on a five-year mission to explore a distant planet, but an act of sabotage by the scheming Dr. Zachary Smith - who managed to get himself trapped aboard the spaceship - leaves them adrift in space for three years. The Robinsons, pilot Don West, Dr. Smith and their trusty robot move from planet to planet, always searching for a way to return to Earth.
As the Jupiter 2 prepares to launch, Colonel Dr. Smith comes on board and ends up being trapped onboard during blastoff. Because of him being there, the Jupiter 2 careens off course and becomes lost in space.
The Jupiter 2 is pulled into a giant ship occupied by bubble-like creatures.
While spacewalking Doctor Robinson is pulled down onto a planet. Major West lands the ship to search for him.
Due to the planet's orbit, the Robinsons are going to freeze to death unless they head south.
After experiencing the extreme cold, the planet gets closer to the sun, roasting it. Smith sends the robot to warn the Robinsons.
The Robinsons meet a fellow Earth explorer who is also lost in space. They help him repair his ship and ask him to take Will and Penny home.
Penny strikes up a friendship with a deep voice in a deep cave.
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."
The Robinsons face dangers on strange terrain, where water is running low and the heat is getting more intense.
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 and Dr. Smith come upon an alien machine that grants wishes, which tests the values of the Robinson group.
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."
With the men off on a mission, the Robinson women must deal with an alien intruder.
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.
Trying to contact his Uncle Thaddeus during a séance, Doctor Smith summons a ghostly monster native to the planet.
After the Robinsons repair a damaged robot, it first helps them and then plots to capture them.
During a cosmic storm, Dr. Smith and Penny discover a strange mirror. Dr. Smith becomes interested in the mirror because it has platinum in it. Meanwhile Penny gets very emotional and wants to stay the way she is when Judy tells her she should dress feminine once in a while. Later Debbie the Bloop is followed into the strange mirror where a pocket universe with a odd boy is discovered.
John and Will fight a battle with an alien father and son that is to the death.
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.
Doctor Smith delights that he is made ruler of an alien species until he learns that he is also their sacrifice.
The Robinsons run into a group of space hillbillies whom Zachary believes might take him back to Earth.
Dr. Smith and Penny obtain a ring that will turn anything to platinum.
Will awakes a sleeping princess whom he now must marry. Her race has been awakened and now plans to conquer the universe starting with Earth.
A strange interdimensional ship turns Will into a genius and Dr. Smith into an old man.
An evil spirit possesses John Robinson and plans to fly the Jupiter 2 back to his home world, even at the expense of Will's life.
Dr Smith and Will befriend an old miner named Nerim. After a series of earthquakes indicates that the planet is breaking up, Dr Smith tries to convince them that it is merely the effects of mining, and no harm will come to the planet. John informs him that he is wrong and that the Robinson family will be departing within the day. It is a race against time to escape the crumbling planet.
Shortly after leaving their original crash-site planet, Smith spots a familiar star and, in an amazing show of stellar navigational skill, calculates the course to get back to Earth. He extracts a promise from Don and John that they'll return to Earth, or else he'll destroy his navigation data. They agree, but inform the family at dinnertime that they are headed for Alpha Centauri after all, mainly because the Earth is on the other side of the Sun (how do they know that? - do they know the date? And besides, from Alpha Centauri, Earth revolves clockwise, visible all the time). Smith changes course 180 degrees, then clumsily jettisons most of the fuel. They reach a refueling barge, one of several that Alpha Control put out in 1996, top up the tanks, and resume course for Alpha Centauri, not knowing that they've picked up a tailgater who follows them after Smith reverses course to Earth again. The alarm goes off in the night, and they expend a lot of fuel pulling away from the Earth's
The Robinsons leave their planet to escape a collision with a comet and find a ship full of frozen convicts.
Passing through a time warp, the Robinsons do return to Earth in the year 1947. They are mistaken as invaders and start the UFO scare of the 194
A spaceship requests medical help for their computer and Dr. Smith has to perform brain surgery on it.
Complete episode guide for Irwin Allen's Lost in Space with detailed information about every season and episode including air dates, summaries, ratings, and streaming availability in United States.
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Due to Smith's actions the crew has had to land their ship on an alien planet which is run by cyborgs. Meanwhile the crew try to break free from the captors who promise them power and luxury and they have to save their robot who was crippled by a ray gun.
The Robinsons encounter a hermit who plans to attack the Jupiter 2 with his army.
A space circus comes to town and the owner wants Will to run away with it.
The Robinsons are tried for space crimes and the evidence shows that Smith is really responsible for the mishaps.
Doctor Smith creates an android that they teach to be more human. A humanoid shows up looking for payment for the android.
Dr. Smith ends up in a boxing match with some space gladiators. If he wins he will return to Earth, and if he loses it won't matter because Earth won't be there.
Will, Penny and Dr. Smith get involved with a thief that is searching for a princess
Jeremiah Smith shows up to kill Doctor Smith for his inheritance.
Will and Doctor Smith are out and about and a swift gun named Xeno who is on the run from the law and happens to be a exact double for Dr. Smith trades places with him allowing the real Dr. Smith to be arrested in his place.
Doctor Smith while out with Will discovers a golden Lyre on a pedestal in a stone arch. He strums it and is sent to what appears to be Hell.
The mysterious Saticon's make a offer to the Robinsons to buy the robot. The offer is turned down and then in the middle of the night the robot disappears. Later it is discovered that the Saticon's are more than they seem.
Sesmar cons Doctor Smith into using a special camera to take pictures of the Robinsons. They're personalities are then stolen from them for use in a Frankenstein type android that Sesmar is in the process of creating.
Beauty meets the beast, two aliens fighting a war land on the planet and the Robinsons are stuck in the middle of things. Handsome golden man Keema and the frog faced alien have the Robinson's choosing sides, will it be the right one?
Athena, the green girl from "Wild Adventure" who lured Doctor Smith out into space, returns and is still in love with him. Her suitor from the Green dimension follows her and turns Will green.
Sagramonte a knight errant, comes to the planet in search of Gundemar The Questing Beast. He then takes Dr. Smith and Will hostage.
Doctor Smith and Will discover a old android machine from the Celestial Department store and end up getting sucked into the machine. There they meet a toymaker who refuses to believe that they are both human.
A space pirate looking for his crew that mutinied finds Will and Dr. Smith trying to repair his empty ship.
Through some harmless playacting, Dr. Smith unintentionally conjures up the magical gauntlets and war hammer of the Norse god Thor. Taking him for a mighty warrior, Brynhilda spirits Smith off to Asgard for a showdown with Thor.
Smith is keen for the job of sorcerer's apprentice after learning that a space magician's rocket ship can reach Earth in a few hours.
Shortly before lift-off, Dr. Smith discovers a cave inhabited by devices, which are the remnants of a once-mighty civilization; the Draconians. As the countdown draws near, Dr. Smith falls ever-more-so under the influence of the Draconians.
Dr. Smith, Penny and Will are out playing a game and Penny finds a gold coin on the game board. They then find a trail of the gold coins and Dr. Smith falls into a cave containing a skeleton of an alien along with a old treasure chest. The Robinsons then have another encounter with the notorious space pirate Captain Tucker.
In the second of two sequels to Lost in Space: The Android Machine (1966), Verda's sheltered by the Robinsons after she's marked for destruction by the Celestial Department Store. To that end, the store dispatches a killer android: IDAK (Instant Destroyer And Killer).
A female alien meets the Robinsons and uses them to help erect an arch to bring her people to colonize the Robinsons' planet.
While in the Valley of Shadows the Robot is affected by strange forces and grows to the size of a building. Will and Dr. Smith enter the Robot to try to reverse the process and save him.
While John and Maureen are away observing volcanic activity, the alien scientist Lemnoc captures Don, Judy, Penny, and Dr. Smith and replaces them with android duplicates. Lemnoc then forces Will and the Robot to train the duplicates in survival skills, hoping that they will be an inspiration to his own people, who are losing the will to live.
The planet is invaded by an army of tiny robots who closely resemble the Robinsons' Robot and proclaim him as their long-predicted king. The Robot agrees to become their king, but when he is not the ruthless ruler they expected, they decide that he needs some "Dr. Smith" in him.
Will and Dr. Smith find a cave that transports them to Earth, 19th-century Scotland.
Penny will not give up the belt entrusted to her by an alien even if it means their deaths
After killing a hostile alien, Professor Robinson comes across a "hunter" and he must replace his dead prey.
On a planet where a primitive people are ruled by a computer, Doctor Smith goes against character and saves Major West's life.
Using an alien machine Doctor Smith creates an army of cyborgs to conquer the universe.
The Robinsons take a boy home to his planet and come across a spaceship that is a space lighthouse. The boy gets angry when they tell him they don't have enough fuel to get him home.
Accidentally landing on a planet, Will, Doctor Smith and the Robot find the Jupiter 2 is now an archaeological site and that they are in the future.
A group of space hippies is going to destroy the planet the Robinsons are on.
When a gaseous creature engulfs the Jupiter 2, the other crew members disappear leaving Will and Doctor Smith alone.
The Robot "falls in love" with an evil female robot sought by two aliens.
Galaxic showman Farnum B. wants to exhibit the Robinsons in his zoo.
Two escaped thieves transform themselves into humans and pretend to be tourists as Smith turns the Jupiter 2 into a hotel.
Will meets a princess who is escaping two bounty hunters, yet Will gets kidnapped instead.
John Robinson and Don West are transported onto a strange new world where their evil opposites exist and plan to change places with them. Will, the Robot and a reluctant Dr. Smith set out to find and help the real Don and John only to be pursued by an evil John Robinson.
Landing on a planet some shapeless beings duplicate the Robinsons and take the Jupiter 2 with the intent of conquering Earth. Will gets aboard to stop them.
Penny is kidnapped by aliens who think that she is the missing Princess Alpha.
After making a deal with the Time Merchant, Dr. Smith returns to Earth just before the launch of the Jupiter II. If he doesn't get on it, the Jupiter II will crash into an asteroid.
When the Robinsons nearly reach Alpha Centauri, they find a human base run by young people. They convince the adults that Penny and Will aren't their children and they leave in the Jupiter 2.
Don and Doctor Smith are sent to an intergalactic prison after coming across an escapee.
Farnum B, the intergalactic showman, again encounters the Robinsons as he presents the Galaxy Beauty Pageant, and its sponsor wants Judy to enter - and win.
Doctor Smith disposes of a plant which has grown to an intense size, and becomes attached to the hull of the Jupiter 2.
Smith lands the pod on a planet where plants are the highest form of intelligence. The Robinsons land only to be captured by Tybo, a giant carrot. He plans to turn them into trees while Dr. Smith becomes a stalk of celery.
With the Robinsons running out of food, Dr. Smith trades the ship and the Robot to a junk man for food.