"Trip Through The Robot"
Trip through the robot.jpg
LiS episode
2x26 / 55th of 83 aired
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Last week, as you recall, we left our space pioneers checking their electrical system - unaware that Dr. Smith's carelessness could result in the fatal destruction of their faithful Robot...


The episode begins with Professor Robinson and Major West doing a complicated test of the Jupiter 2's electrical systems. They rely on Dr. Smith for assistance, and the resulting accident causes extensive damage to the spaceship.

The first side effect of the accident is that the Robot cannot be recharged. Disconsolate, he leaves the campsite and wanders away. He falls over, and due to a malfunction in his "ionic processor" he grows to enormous size.

Will and Smith discover the Robot in this state and go inside him to reverse the "ionic processor" in order to shrink him back down to normal size. Eventually Professor Robinson and Major West follow them into the Robot in order to rescue them. In the end everyone escapes from inside the Robot, and the Robot returns to his normal size.

The Robot enlarges to a fantastic size, and Will and Smith crawl inside to reverse the process. Dr. Smith punches the wrong buttons on the Jupiter 2's main power units, and causes a disastrous explosion. He has also forgotten to recharge the Robot, who is failing pitifully. Will appeals to his father to hook him up to the emergency power so he will not die, but John is afraid it might overtax the unit. Penny finds a taped message from the Robot, saying that he is simply going away rather than cause them further anguish. Will awakens Smith during the night to help him search for this friend.

They find the Robot enlarged to the size of a house. The boy realizes the valley mists have reversed his ionic processes and thinks he can get inside and switch him back to his normal size. Will enters the Robot through an opening near the treads and, with Smith close behind, tries to find his way past machinery now bewilderingly unfamiliar in its enlarged state. An infrared heat-seeking laser unit, pro- grammed to destroy an alien body inside the Robot, comes to drive them out.

Separating, Will tries to find his way along the audio canal to the computer area where he works on reversing the ionization. While John and Don are searching for Will, Smith gets sucked into a temperature control tube, but is saved when the Robot bravely expends most of its remaining energy to expel him. John and Don find their way inside. As they fight t the hazards within, Smith tells Will there is no hope. But in that moment Will remembers the Robot has a reverse power unit, and hooks it up before the heart freezes. Will next switches the power to the treads and completes the reversal of the ionic processes.

As the Robot starts to shrink, Smith flees for the exit and runs into John and Don. Cravenly forestalling any delay in getting out by telling them Will is already outside, he leads the two to the opening and they barely manage to get through the shrinking aperture. In truth, the boy is having a frightful time crawling through passages that are rapidly growing smaller, but he, at length, makes the exit and gets out. Happily they return to camp, where the Robot isrecharged.

A very well written episode. Smith and Will save the Robots life in this one. A favorite among LIS fans,in it is yet another take off on the Fantastic Voyage plot of someone,invading a larger body,such used in Star Trek episode The Immunity Syndrome, as the star ship Enterprise invade the alien void of the space ameba and with V'Ger,in Star Trek the Motion Picture. .

Background Information

  • Many props from other episodes are used to represent the Robot's internal workings. Most noticeable is the Purification Arch prop from The Colonists.¬† In this respect the episode could be what is called in the TV industry¬† a "bottle show" - a script that can be filmed cheaply as it uses existing props, sets, special effects, and a minimum cast.¬† Bottle shows are typically kept in reserve in case a committed script becomes undoable and something is needed at the last minute or in order to bring production costs back under control.
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