Lost in Space (1965–1968)
4 user 1 critic

Forbidden World 

On their next planetary stop the Robinsons encounter a hermit that plans to attack the Jupiter 2 with his army.



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Episode complete credited cast:
... Prof. John Robinson
... Maureen Robinson
... Maj. Don West
... Judy Robinson
... Will Robinson (as Billy Mumy)
... Penny Robinson
... Dr. Zachary Smith
... Tiabo


On their next planetary stop the Robinsons encounter a hermit that plans to attack the Jupiter 2 with his army.

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Release Date:

5 October 1966 (USA)  »

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Technical Specs


Sound Mix:

(RCA Sound Recording)


Aspect Ratio:

1.33 : 1
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Did You Know?


The formula for the "high explosive" that Dr. Smith drinks is given as C3H5HO2. This is the formula for propionic acid, the substance that gives stale sweat its distinctive smell. Seems very unlikely that Smith would find this as pleasant to drink as he did in the show. It's not explosive either. Scientific accuracy was never a high priority for the script writers, but could this be an "in joke" on the part of the writers. See more »


You would think that the Robot would be able to test whether or not Dr. Smith could still explode. Instead he engages the detonator to get the result, with Will standing right beside Smith. See more »


Penny Robinson: Poor Dr. Smith. All he does is sit on a rock and stare off into space.
The Robot: According to my calculations, he must stay 50 yards away from all members of this party.
Penny Robinson: Are you sure there's a chance of him blowing up?
The Robot: The answer is positive. Dr. Smith has consumed a quart and a half of explosive. That gives him a concussion power of 15 sticks of dynamite.
Maj. Don West: Well, Dr. Smith isn't our only problem.
Prof. John Robinson: We got to get this force field working.
Maj. Don West: Let's give it a try.
Prof. John Robinson: All right.
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User Reviews

Another solid adventure, a 4.9 on my personal scale, and #23-ranked of the season..
6 October 2012 | by See all my reviews

"Forbidden World" is my lowest ranked of the four Season Two episodes so far, but not by a whole lot really. The episode has one of the very best (perhaps #1) and most intense opening teasers of any episode. Of course, it slows down after that somewhat, but not at all in a bad way. The episode is played quite straight and serious, in keeping with the B&W Season One feel so far. For some reason, "Forbidden World" seems to get kind of a 'bad rap' a lot, and you know the reason.."Big Bird," "The Parrot Creature," "The Chicken Monster." Well, I have seen all three of these terms used. The great costume designer Janos Prohaska designed that bird, and I am assuming it was him in the costume as well. Janos Prohaska designed and played like three creatures in STAR TREK, one from each season, as I recall. Overall, "The Parrot Creature" (take your pick and call it what you will) is not really bad at all. There is nothing really bad or overly 'silly' about the creature. He is kind of cute, actually. These are alien worlds in the sci-fi universe, so who is to say what is out there? Besides, the creature does not talk with a female voice like the pink dragon Gundemar. So, you have got to give him/it credit for that.

"Forbidden World" is Barney Slater's first script this season, and he would be very active this year. Also very active by this time in the series was director Don Richardson, and this was his second input of the season. Guest star Wally Cox as "Tiabo," although nothing to get too scared about, was basically a serious character who meant business. He was just a scared and loner type quirky hermit. Really, LOST IN SPACE is still serious at this point..but it is about to gradually, gradually delve into the BATMAN style more comedic "LIS Lite" episodes.

Robert Drasnin is the guest composer here. The music is obviously not up to Johnny Williams style standards, but it is not bad and it works well with the story and with the quirky guest characters. This is another middle-of-the-road Season Two adventure for me, but slightly down into the lower half here. Season One and Season Two are now both officially 'grounded,' as far as an alien planet goes. But, as you know, the Jupiter Two will clippity-clop all across the heavens during its shorter Season Three run. Speaking of 'clippity-clop,' this is the very first episode where we hear the infamous Robert Drasnin "clippity-clop weeeeeeeeee" music at the very end.




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