Star Trek (1966–1969)
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The Alternative Factor 

Existence itself comes under threat from a man's power-struggle with his alternate self, with the Enterprise's strained dilithium crystals presenting his key to a final solution.



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Episode complete credited cast:
Charlene Masters
Assistant Engineer
Christian Patrick ...


While investigating and scanning an uncharted planet, the Enterprise and its quadrant of space are subjected to a violent force that seems to cause a 'blinking out' of everything near them. When the scanners resume, where once there was no life on the planet, now there is one life sign. Kirk, Spock and a security force beam down to investigate and find a man named Lazarus who collapses and is brought aboard the Enterprise for treatment. To complicate things further, the initial phenomenon almost totally drained their dilithium crystals. Starfleet and Kirk suspect this phenomenon could be a prelude to invasion. While interrogating Lazarus he tells Kirk that he's locked in a struggle with another being who is 'anti life' and is behind the phenomenon. The disruptions continue to occur and the ship's situation grows worse. Written by tomtrekp

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Release Date:

30 March 1967 (USA)  »

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Aspect Ratio:

1.33 : 1
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Did You Know?


When Lazarus sabotages the Engineering Panel, the electrical plugs he switches around are actually Dual Binding Post Plugs, very common when this show was made in the 1960s and still in use today. See more »


When Lazarus leaves his bed in the sickbay at around the 30 minute mark, the bed continues to broadcast his heartbeat. Indeed, when he starts to have an attack, his heartbeat speeds up. Normally, the sickbay bed can only read a person when he is lying on it; the sound should have stopped as soon as he stood up. See more »


Lazarus: He'll kill us all if you don't kill him first! Kill! Kill! Kill! Kill! Kill!
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Crazy Credits

The closing credits are set against a combination background of stills from that episode and previous episodes. See more »


Referenced in Galaxy Quest (1999) See more »


Theme From Star Trek
Written by Alexander Courage
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User Reviews

Lazarus Blinks and the Universe Disappears
30 July 2006 | by (United States) – See all my reviews

The threat which Kirk and the Federation face here is nothing less than the complete annihilation of our entire universe - surely the gravest cosmic problem encountered in Trek's history. It's one of those wild cosmic concepts more prevalent on the TNG series, not restricted to a quadrant or even just our galaxy, but everything. However, the execution of this story and the faulty pace of this episode is rather deplorable. There's way too much repetition throughout: Kirk and some crew beam down to a planet's surface, they go back up to the Enterprise, then back down to the planet, over & over, it seems, with no results; Lazarus falls off a cliff a 2nd time...or is it a 3rd? Much of the attempted efforts to explain the dangerous cosmic effect come off as gobbledygook - is it a doorway in space? A hole between two universes? A corridor with explosions at both ends? Say what? There's also confusion on whether Kirk is dealing with a time traveler here or hopping to parallel dimensions (better realized in "Mirror,Mirror" early in the 2nd season). I finally gathered in the end that the threat revolved around matter and anti-matter of two duplicate objects coming together; but, boy, what a headache to get there.

Kirk, Spock and the others encounter a weird guy named Lazarus on a barren planet following a 'winking out' of all existence. He rants on about his nemesis, an enemy which looks humanoid but is a monster. By the 2nd act, we realize this Lazarus is insane, but Kirk & especially McCoy aren't so quick on the uptake, while Spock just calls him a liar. After a few very spacey phrases by this Lazarus, I would think they'd realize the guy's not all there when Lazarus says "Kill! Kill! Kill! Kill! Kill!" Yet, as in a few other weak episodes, an obvious nutcase like this one is given free reign within the Enterprise and this causes problems later (I think Kirk did assign security at some point, but they lost Lazarus a minute later). Then we get that 'cosmic effect' and negative images in slow motion for the 4th or 5th time, meant to convey a struggle between - wait for it - two Lazarus dudes! And as we all know, two into one won't go. This episode gets my vote for the worst one of the first season, a precursor to all those really bad, boring ones in the third season. I do give it more stars than those due to a genuinely chilling denouement at the conclusion.

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