Lost in Space (1965–1968)
3 user 2 critic

Attack of the Monster Plants 

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.


Justus Addiss





Episode cast overview:
Guy Williams ... Prof. John Robinson
June Lockhart ... Maureen Robinson
Mark Goddard ... Maj. Don West
Marta Kristen ... Judy Robinson / Duplicate Judy
Bill Mumy ... Will Robinson (as Billy Mumy)
Angela Cartwright ... Penny Robinson
Jonathan Harris ... Dr. Zachary Smith


As the Robinsons accumulate the last amounts of fuel needed for lift off, Smith is expelled from the camp when his cowardice and sloth nearly costs the men's lives. John is undecided about taking Smith when they leave, but the doctor discovers that the peculiar reproductive habits of alien cyclamen plants might give him the upper hand. Written by Mister-UHF

Plot Summary | Add Synopsis


Not Rated | See all certifications »




Release Date:

15 December 1965 (USA) See more »

Company Credits

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Technical Specs


Sound Mix:

Mono (RCA Sound Recording)

Aspect Ratio:

1.33 : 1
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Did You Know?


The show did not address the question of what happened to the Duplicate Judy after the real Judy is found. See more »


The stem of the duplicating plant Dr. Smith was showing to Will is actually a vent pipe for a clothes drier. See more »


Dr. Zachary Smith: All right, gentlemen, there's no room for goldbricking in this operation. Let's get on with it, shall we?
See more »

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User Reviews

Judy's Hour To Shine
12 February 2015 | by StuOzSee all my reviews

A double of Judy is created from a monster plant.

When seen in my 1970s childhood this hour was at times powerful drama and at times strong horror. The quicksand footage and the Judy swallowed by plant footage was heavy stuff when I was a kid. Sadly, the impact of this hour has softened to my now 40something mind.

Attack Of The Monster Plants is still enjoyed, but not as much as before.

Nice to see Judy get something to do for once, the poor girl spent so much of the series just standing around in the background. In season's two's A Visit To Hades she got more to do, but in one scene she cried like a child. Whatever the case, Attack Of The Monster Plants is Judy's hour to shine in Lost In Space.

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