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

Plot Summary | Plot Synopsis


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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?


Unlike in the earlier Star Trek: Mudd's Women (1966), dilithium crystals are portrayed here as translucent amber slabs, which conveniently fit in the energy panels of Lazarus' ship. The universality of the amber-slab dilithium crystal mount connector as being common to both the Enterprise and to Lazarus' timeship, suggests a commonality in the manufacture and sourcing of at least its dilithium crystal converter assembly. There is also no mention in this episode of bypass circuits being fused beyond useabilty as a power-conversion alternative, the existence of which were mentioned to bolster the direness of the need for replacement crystals in the storyline of Star Trek: Mudd's Women (1966). Dilithium crystals, in their natural state, however, are depicted as resembling quartz crystals in both Star Trek: Mudd's Women (1966) and Star Trek: Elaan of Troyius (1968), suggesting that the amber-slab devices depicted in this episode are themselves some kind of mounting structure, the translucent glow meant to depict the power flow somehow being transformed by being focused through the crystal or crystals contained within. The amber slabs are, however, explicitly referred to in dialogue as being the crystals themselves. See more »


Lazarus never introduces himself by name on screen to Kirk, yet Kirk calls him by name during the first planet search. We come into Kirk's interrogation of Lazarus part way through. There is no way we can know exactly when Kirk learned Lazarus' name. See more »


Charlene Masters: Report on the Dilithium crystals, Captain.
Capt. Kirk: Yes?
Charlene Masters: Whatever that phenomenon was, it drained almost all of our crystals completely. It could mean trouble.
Capt. Kirk: You have a talent for understatement, Lieutenant. Without full crystal power, our orbit will begin to decay in ten hours. Re-amplify immediately.
Charlene Masters: Aye aye, sir.
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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

Weird Goatee Beard Changes - Thicker Then Thinner
26 February 2007 | by (London) – See all my reviews

I love these old STAR TREK episodes but this must be one of the lamest ever. I couldn't figure out what on earth was going on - nor could Kirk and Spock by the sound of them. Spock keeps making strange and frankly incomprehensible statements like "it's possible...very possible." It's either possible or not, make up your mind, Mr Spock.

Meanwhile, a man falls off a cliff, again and again, and is cured by a small plaster, though blood drips from his mouth. The best parts are Kirk's line "I want facts, not poetry!" and the Enterprise crew hanging out in the recreation room smirking at the state of the canteen coffee while the goatee man prowls about looking ragged. Couldn't Bones have loaned him a spare suit at least?

It's still all splendid fun, of course, and I recommend it wholeheartedly over all modern TV programmes.

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