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

West of Mars 

Zeno, an intergalactic gun fighter, is Doctor Smith's doppelgänger, and he switches places with Smith. Smith confesses to Zeno's crimes out of fear.


Nathan Juran


Michael Fessier, Irwin Allen (created by)

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Episode complete credited cast:
Guy Williams ... Prof. John Robinson
June Lockhart ... Maureen Robinson
Mark Goddard ... Maj. Don West
Marta Kristen ... Judy Robinson
Bill Mumy ... Will Robinson (as Billy Mumy)
Angela Cartwright ... Penny Robinson
Jonathan Harris ... Dr. Zachary Smith / Zeno
Allan Melvin ... Enforcer Claudio
Mickey Manners Mickey Manners ... Dee
Ken Mayer ... Pleiades Pete


Zeno, an intergalactic gun fighter, is Doctor Smith's doppelgänger, and he switches places with Smith. Smith confesses to Zeno's crimes out of fear.

Plot Summary | Add Synopsis


Not Rated | See all certifications »




Release Date:

30 November 1966 (USA) See more »

Company Credits

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Technical Specs


Sound Mix:

Mono (RCA Sound Recording)



Aspect Ratio:

1.33 : 1
See full technical specs »

Did You Know?


Favorite episode of Jonathan Harris because of the dual role he got to play. See more »


After changing clothes with Dr Smith and giving him his gun & hat, Zeno pushes Dr Smith towards where he believes Will Robinson to be. Immediately after pushing Dr Smith, the side of Zeno's face can be seen, and it is a stand-in actor. See more »

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User Reviews

Western-themed episode misfires
18 September 2010 | by benkidlingtonSee all my reviews

Intergalactic gunslinger named Zeno lands on the planet with space sheriff in hot pursuit.

Amazingly, Zeno is an exact doppelgänger of Dr Smith which fortuitously allows Jonathan Harris to play the guest alien visitor of the week as well as himself.

The other guest actor playing the sheriff/enforcer is pretty forgettable although there is one humorous character in it "Pleiades Pete" as a purple-shirted rival gunslinger with a mean attitude (played by Lane Bradford) who sadly doesn't get enough screen time. Although, you'll probably think Officer Bolix from the first season is one of the greatest characters the show's ever had after seeing the sub-par performances here.

There is some fun to be had though, but as this episode is well within the silliness phase of season two, coming straight after (the even worse in my opinion) "Curse of Cousin Smith", it's best not to expect too much from it.

I suppose it's easy to be amused as the space enforcer pushes his hands through the plastic drapes of his jail-cell spacecraft to take a navigational sighting, exposing himself and the "cabin" to the vacuum of space. But of course, the series at this point has become something completely different from the attempted realism of the first series which had airlocks, spacesuits, suspended animation and nuclear motors. So, really trying to think in sci-fi terms is no longer appropriate, we are indeed in the realms of pure fantasy/adventure at this point.

Although I got some enjoyment out of this episode, I don't like the way Don West bullies Smith (actually Zeno, but he doesn't know that). We know there's usually some playful animosity between the characters, but the way Don picks a fight by calling him a "Senile Delinquent" just makes his character seem nasty and utterly unlikeable, so much so that you may actually want Zeno to shoot him! Second thing is the exasperation you might feel as no-one can remotely tell the difference between Smith and Zeno. All they would have to do is ask them about any incident that happened in any previous episode. In that case, the real Smith would obviously be immediately identified. Will's confusion about this is particularly unbelievable, and after all they've been through together, quite irritating too.

Still, a must see episode for all die-hard LIS fans, just not a very good one IMHO for reasons given.

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