Lost in Space Wiki
Lost in Space Wiki

This article is about the Robot as seen in the original Lost in Space. For the Robot as seen in the Netflix television series, see here.

The Robot (a B-9 Class M-3 General Utility Non-Theorizing Environmental Control Robot) is a character in the original 1965 television series Lost in Space. Known and addressed simply as "Robot", his full designation was only occasionally mentioned on the show. Occasionally the Robot was addressed with the names of B-9 and the Robinson Robot. Other names for the Robot were Rodney and his creator, Robert Kinoshita, called him Blinky.


Although a machine endowed with superhuman strength and futuristic weaponry, the Robot often displayed human characteristics such as laughter, sadness, and mockery, as well as singing and playing the guitar. The Robot was performed by Bob May in a prop costume built by Bob Stewart. The voice was primarily dubbed by Dick Tufeld, who was also the series' narrator and Jorge Arvizu for the Spanish dubbing. The Robot was designed by Robert Kinoshita, who also designed Forbidden Planet's Robby the Robot. Robby appears in Lost in Space episode #20 "War of the Robots" and in episode #60 "Condemned of Space." The Robot did not appear in the unaired pilot episode, but was added to the series once it had been greenlit. Initially, the bellows-covered legs were articulated and moved separately by the actor inside, but the metal edges inside the suit cut actor Bob May's legs so changes were made. The legs were bolted together, and the robot was pulled along by a wire instead of walking as it had done before. A new lower section was constructed with the legs cut off at the knee. This shorter suit was used to film close-ups or when the Robot was standing behind something that hid the actor's legs protruding out the bottom. This version of the suit was informally referred to by the cast and crew as "the Bermuda shorts."

Features and Abilities[]

Robot B-9 consisted, from top down, of a glass bubble sensor unit with moving antennae; a fluted, translucent ring collar (actually an arrangement of shaped ribs through which performer Bob May could see); and a cylindrical, rotating trunk section with extending bellows arms that terminated in red mechanical claws. The trunk section had controls, indicators, a removable power pack and a signature chest light that illuminated in synchrony with the Robot's speech. May had a key inside the suit located in the left hook that he would tap in time with his speech to illuminate the light, resulting in some scenes where one of the claws can be seen moving in time with the light. Below the trunk were the bellows legs that were understood to move with some agility but which were rarely seen on camera to move separately due to real-world practical limitations, and trapezoidal tread-tractor units at the bottom of each leg. These normally worked as a single locomotive device, but they could also function as individual feet. The leg and tractor sections could apparently be readily detached, allowing the Robot to be positioned in the rear of the chariot, although the actual disconnect operation was depicted only once. According to the series, the Robot possessed powerful computers that allowed him to perform complex calculations and to deduce many facts. He had a variety of sensors that detected numerous phenomena and dangers. He was programmed with extensive knowledge on many subjects, including how to operate the Jupiter 2 spaceship (although in the episode "The Hungry Sea" the Robot states categorically that it is not programmed to pilot the ship). His construction allowed him to function in extreme environments and in the vacuum of space. He was extremely strong, giving him utility both in performing difficult labor and in fighting when necessary. Moreover, his claws could fire laser beams and, most frequently, a powerful "electro-force" that was similar to arcing electricity. In one first season episode, Dr. Smith was seen to remove the robot's programming tapes, which resemble a small reel of magnetic tape, from a hatch below the robot's chest panel.

After Lost in Space[]

Two versions of the robot were used during Lost in Space filming, a "hero robot" costume worn by Bob May, and a static "stunt robot" prop that was used for distant or hazardous shots. Both versions fell into disrepair after the series but they have since been discovered and restored. The "hero robot" is privately owned by TV and film producer Kevin Burns who commissioned a replica in the early 1990s for touring and conventions. The "stunt robot" is in storage at the Science Fiction Museum and Hall of Fame in Seattle, Washington. Like Robby the Robot, the B-9 Robot prop costume was re-used on at least one other show. On the Saturday morning children's show Mystery Island, it was modified to create the primary character P.O.P.S. It had different domes, a different color scheme, and an added rectangular skirt of gold-colored tubes covering the rubber bellows legs and base. Full-sized replicas of the robot are available commercially. Other versions have been built by hobbyists around the world who have built at least 15 detailed full-size replicas of the Robot.

Extra Information[]

Was the Robinsons' trusted Robot more than he appeared to be? Perhaps even extraterrestrial in origin? There are some hints at the use of extraterrestrial technology in the construction of the Robot, but many of the instances can be more simply explained.


-In "War of the Robots," the Robot knows what a robotoid is and seems to know that they are dangerous right from the start; he even seems to be able to track it a bit at the beginning of the episode.
-The Robot seems to know right away that the masked John Robinson is not the alien himself in the last half of "Follow the Leader." He also knows this alien is a spirit.
-In "The Ghost Planet,” the alien machines are well aware of the existence of the Robot and he doesn't seem too surprised by them. They seem to know each other or at least of each other's existence.
-In “The Ghost Planet,” the Robot also knows that the missile fired by the planet is hyper-atomic.
-In “The Golden Man,” the Robot knows the ratings of alien minefield bombs.
-In “A Visit to Hades,” the Robot recognizes Morbus as an alien right away.
-In “Hunter's Moon,” the Robot knows a bit too much about Megazor and his culture and that Earthlings are not natural enemies of the Zon culture.
-In "Flight Into the Future,” the Robot seems to know the illusions are not real.
-In “A Day at the Zoo,” Robot seems to know what Farnum's alien flower trap will do.
-In “The Anti-matter Man,” the Robot knows quite a lot about the anti-matter universe.
-In “Fugitives in Space,” the Robot knows Space Law.

Rebuttal: All of the above can be explained by the Robot's use of his sensors, superior analytical ability, or the application and extrapolation of knowledge programmed into him. The Robot's familiarity with alien cultures may be attributed to 'off-screen' communication.


-In "A Change of Space," the Robot can communicate with the alien.
-In “Wild Adventure,” the Robot can translate for Athena.
-In “The Girl from the Green Dimension,” the Robot can translate for Urso.
-In "Kidnapped in Space,” the Robot can communicate with the alien machine and operate on it.
-In “Condemned of Space,” the Robot communicates with the alien robot.
-In “Castles in Space,” the Robot translates for the Princess.

Rebuttal: In “Invaders from the Fifth Dimension,” the Robot reveals he can 'read minds' by translating the electromagnetic waves of human thought back into words; this could also apply to sentient alien species. In several episodes, the Robot states that an alien language (and this applies to alien machines as well) is based on mathematical principles; since mathematics is broadly considered a 'universal language,' the Robot is able to use it to establish communication.


-In "Return from Outer Space," the Robot can work the matter transfer unit.
-In “Wreck of the Robot,” the aliens know how to take the Robot apart without damaging him.
-In “Revolt of the Androids,” the Robot can repair IDAK Alpha 12.
-In “The Space Primevals,” the Robot can make things vanish and reappear.
-In “Junkyard in Space,” the Robot's parts are compatible with the Junkman's.

Rebuttal: If humans can figure out alien technology, even if only by trial and error, the Robot should be able to do so as well, and more quickly too. The instances above must also be considered in the light of the points raised above: the Robot's use of his sensors to gather information, his superior analytical abilities, and the knowledge already in his possession from which he can extrapolate.

Not Really a Problem

-In “The Dream Monster,” the Robot can beat Raddion.
-In "Trip Through the Robot," despite having had put the Robot together at least twice, Will, Smith, Don, and John do not recognize a lot of the areas and components; is that because they alien or just different due to the enlargement?
-In "The Challenge," the aliens don't seem too worried about the Robot.
-In “Princess of Space,” the Robot was used as a hiding spot for the alien baby princess by her nurse at some point before the events related in the episode "The Reluctant Stowaway."

Rebuttal: The matter of extreme enlargement is sufficient to explain the Robinsons' puzzlement in “Trip Through the Robot.” The points raised in “The Challenge” and “The Dream Monster” do not speak either for or against an alien origin for the Robot. The real problem raised by “Princess of Space” is not that there may be alien technology in the Robot. What is in the Robot is simply a tape that has been hidden; it is not a functioning part of his mechanism. The real question here is how the alien nurse managed to secrete the tape there before the Jupiter 2's lift-off and why she chose the location she did.

The Only Unresolved Mystery

-In "The Mechanical Men,” it is suggested that alien technology may have been used to create the little alien robots as well as the Robot; it cannot be just coincidence that the Robot and the tiny robots are exactly the same in so many ways.

Comment: In “The Mechanical Men,” the Robot himself hints that he knows the explanation to the unexplained similarity, but this is never revealed. It is not a question of whether the mechanical men are the products of alien technology; rather, the question is why they look like the Robot or vice versa. This thus remains the only insoluble mystery regarding the origin of the Robot.

If that's not enough, the Robot just seems to know a bit too much about all the alien cultures encountered, enough to make one wonder. At times, he seems to surprise the family, even Will and John, with what he knows, and even Smith is at times surprised to find out what Robot knows and can do.

  • The Robot, Will says in 1998, was built only two and a half years ago in "Trip Through the Robot." He develops more in "War of the Robots" and later both Will and John admit that the Robot is not quite a machine but something between a machine and a man. The Robot has certainly developed human emotions of a sort by "The Wreck of the Robot," and would miss Smith and Will if either left or if he left either of them. This is seen in "Rocket to Earth" and "The Mechanical Men."
  • The Robot tried to convince himself he was not jealous of Verda (which he was but he did vote to keep her with the Robinsons).
  • The Robot starts acting more like Dr. Smith in the second season, picking up some of his phrases such as, "Hey, wait for me!" in "Treasure of the Lost Planet," as well as some of Smith's fear displayed in "The Toymaker," when Robot says, "I feel sick."
  • The Robot, in "Treasure of the Lost Planet," also says, "The final indignity", another Smith phrase, when Smith used him as a roulette wheel. The Robot also developed a sense of humor in "War of the Robots—" "bad, very bad," and "Excuse me, I think I'm going to be sick!" and in "The Prisoners of Space" in response to Smith's bragging that he has only a few minor faults.
  • In "The Space Primevals," the Robot also admits to Will that Dr. Smith's "timidity can be infectious." This happened after Will noticed Robot sounded a lot like Dr. Smith after warning Will that their trip might be fraught with danger.
  • The Robot claims in "Kidnapped in Space" that he took two semesters of medical training at the Institute of Cybernetics (Don says two years of training). He graduated first in his class. This was all before he became interested in Space Exploration and switched his major (?)! He also tells Will that if he can reactivate his programming tapes on medical knowledge, he can do them proud by operating on the alien clock leader of the Xenians.
  • The Robot's relationships with Will and Smith is more complex than they seem. He has a love-hate relationship with Dr. Smith going on in all the seasons, but also admits that Smith is a great, decent human being and a credit to their expedition. The Robot also admits that Smith is his mentor and that he has a deep affection for Dr. Smith, yet Smith continues to treat him as badly as he did in "War of the Robots" (for which mistreatment Dr. Smith must polish the Robot for two weeks).
  • Smith continues to be cruel or unthinking in "Trip Through the Robot," but manages to try to start the diode timer for Will, seeing how much the boy cares. In "Rocket to Earth," Smith admits the lovable old ninny did have one or two good qualities about him. During the same episode the Robot says, "Oh, Dr. Smith, don't go. We need you."
  • The Robot was staying with Smith in "Cave of the Wizards." He carries Smith on his treads in the same episode and sometimes offers to do the same in others.
  • The Robinsons, Don (who has a pretty good knowledge of the Robot when he is normal size), and Smith probably have taken parts from other computers and robots to use in the Robot. They may have copied tapes from other robots and alien devices into their Robot. This could explain why the Robot knows so much more about alien law and such starting from late in the first season, in the second season, and much more in the third season. Such parts or sharing of information could have come from the robotoid in "War of the Robots," and the alien robots in "The Ghost Planet" may have shared their tapes with the Robot. In addition, the Robot may have shared information with the robot guard and used spare parts from the Verah Castle in "Condemned of Space."
  • Don, Will, and John put the Robot back together in "The Wreck of the Robot." Smith puts him back together in "My Friend, Mr. Nobody." Maureen and Judy work on him in "The Golden Man."


  • In the second season, we discover the Robot's left "eye" blinks red, while the right one blinks green. In the third season, the colors are reversed.
  • The Robot was performed by Bob May in a prop costume built by Bob Stewart. The voice was dubbed by Dick Tufeld, who was also the series' narrator.
  • The Robot was designed by Robert Kinoshita whose other cybernetic claim to fame is as the designer of Forbidden Planet's Robby the Robot. Robby appears in LIS #20 "War of the Robots" and the first episode of season three "Condemned of Space."
  • A modern version of the Robot was the Rambler-Crane Series Robot, which appeared in the Lost in Space movie. The Netflix series which premiered in 2018 features an even more advanced, cyborg-like Robot who is part of a race of similar robots.