(written from a Production point of view)
Investigating the cause of a massive, galaxy-wide disruption in space, the Enterprise finds a mad scientist who claims he is being pursued by a hideous being.
In standard orbit around an iron-silica-type uncharted planet, the USS Enterprise prepares to complete its survey, when the starship is violently rocked twice and everything within sensor range suddenly "blinks", almost as if the universe is on the verge of ceasing to exist. And, in the wake of this, a man appears on the surface of the planet, where moments earlier there was no life.
Beaming down, Captain Kirk, Spock, and the landing party encounter a man. "You came! Thank the heavens, it's not too late!", he exclaims. Dirty and disheveled, he falls from a rock. The landing party returns to the Enterprise with him, where Kirk learns more news – the strange phenomenon drained the dilithium crystals almost completely. Still worse, Starfleet Command issues a Code Factor 1 message – invasion status. The effect experienced by the Enterprise was also experienced everywhere in the galaxy, and far beyond. Starfleet withdraws all nearby ships – Commodore Barstow informs Kirk that the Enterprise is the bait.
In his quarters, Kirk talks to his "guest" – a man named Lazarus, who is pursuing a "thing," a monster who destroyed his entire civilization. He informs Kirk that he will stop at nothing to destroy it. Beaming back down to the planet, Kirk learns from Spock that there is no other creature here. Spock, accusing Lazarus of lying, states "I fail to comprehend your indignation, sir. I have simply made the logical deduction that you are a liar." Kirk demands the truth – and the universe turns inside out once again. The same "winking" phenomenon occurs again. And Lazarus… first he has a bandaged forehead, and then he doesn't, and then he does again.
Meanwhile, Spock has discovered a source of radiation that is not there – a "rip" in the universe, where regular physical laws do not apply. The key to locating this source seems to be the dilithium crystals – a revelation which excites Lazarus, who demands the impossible: that Kirk give him the crystals.
In the briefing room, Kirk confronts Lazarus, but he denies it, blaming his monster. And the evidence suggests he isn't the thief, for the crystals are not aboard his ship. In Sick Bay, Kirk confronts Lazarus with his lies, which Lazarus explains away by claiming that he is a time traveler. The dead world the Enterprise orbits is the distant future of his destroyed homeworld; the place and time he has traveled to in pursuit of the monster. At Dr. McCoy's urging, the crew departs Sick Bay to allow Lazarus to rest and recover from his fall.
Having relocated to the briefing room to consider all of the known evidence, Kirk and Spock conclude that the strange energy must come from a source outside the universe. A source in another, parallel universe. There are two copies of Lazarus, and they are periodically exchanging places through a kind of door – and if they ever exist in the same universe at the same time, everything, everywhere, will be annihilated in a cataclysmic matter/antimatter explosion.
Meanwhile, the alternative Lazarus creates a diversion by starting a fire in main engineering, steals the ship's energy crystals, then beams down. Kirk pursues. As he attempts to enter Lazarus' spaceship, he vanishes, hurled through the corridor into the other universe.
Once there, Kirk meets the other but sane Lazarus-B, and learns the truth. Lazarus-B's people discovered how to pass through the negative magnetic corridor that both connects and protects the two universes. When this happened, Lazarus-A couldn't bear the knowledge that he had a duplicate, and resolved to destroy his opposite. He is mad and doesn't care if this causes the destruction of two universes. Lazarus-B and Kirk realize he must be stopped: if Kirk can force Lazarus-A into the corridor, Lazarus-B can hold him there, and Kirk can destroy his spaceship – which will also destroy Lazarus-B's spaceship. Access to the corridor will be sealed forever and both universes will be safe, but the men named Lazarus will be at each others' throats for the remainder of eternity. Kirk goes back through the corridor and fights in hand-to-hand combat forcibly throwing Lazarus-A into the "dimensional door." Kirk heads back to the Enterprise, ordering Lieutenant Leslie to bring the ship's phasers to target the inter-dimensional ship. The two Lazaruses meet once more and fight as phaser beams vaporize the ship, sealing the two for all of eternity, caught together, between universes. Kirk ruminates on the fact that the two Lazarus are going to be at each other's throats for all time and wonders how it would be. Spock reminds Kirk that the universe is now safe. "For you and me. But, what of Lazarus? What of Lazarus?"
- "Captain's log, stardate 3087.6. While investigating an uncharted planet, the Enterprise, and at least this entire quadrant of space, has been subjected to violent, unexplained stress and force. Sensors have reported the presence of a Human being on the planet below who might be connected with the phenomenon. With my first officer and a security team, I have set out in search of him."
- "Captain's log, stardate 3088.3. We continue to orbit the dead planet, which seems to be the source of the phenomenon which has struck the Enterprise, and all sections of the galaxy, once again. As for Lazarus, the story he tells me about the humanoid continues to trouble me."
- "Captain's log, stardate 3088.7. We are no closer to finding an answer to the strange phenomenon than we were at the beginning. Not only have two of my crewmen been attacked, two of our dilithium crystals are missing, and without them, the Enterprise cannot operate at full power. They must be found."
"I want facts, not poetry."
- - Kirk, after Spock describes the cosmic disturbances as "winking out"
"He's death! Anti-life! He lives to destroy!"
- - Lazarus, on his antimatter counterpart
"I told you, it was the thing! All white, black and empty. A terrible emptiness."
"Let's get back to the ship."
"He'll kill us all if we don't kill him first! Kill! Kill! Kill!! Kill!! Kill!!!"
- - Lazarus and James T. Kirk
"Are you deaf as well as blind?!"
- - Lazarus, to Kirk and company
"I fail to comprehend your indignation, sir. I've simply made the logical deduction that you are a liar."
- - Spock, to Lazarus
"Sometimes pain can drive a man harder than pleasure."
- - Kirk to McCoy, on an injured Lazarus
"Jim, madness has no purpose or reason. But it may have a goal."
- - Spock
"If they meet."
"Annihilation, Jim. Total, complete, absolute annihilation."
- - Kirk and Spock, on the two Lazarus counterparts existing in the same universe
"So you're the terrible thing? The murdering monster? The creature?"
"Yes, captain. Or he is. It depends on your point of view, doesn't it?"
- - Kirk and the antimatter Lazarus
"You'll be trapped inside that corridor with him forever. At each other's throats throughout time."
"Is it such a large price to pay for the safety of two universes?"
- - Kirk and the antimatter Lazarus, on sealing the magnetic corridor
"Captain, the universe is safe."
"For you and me. But what of Lazarus? What of Lazarus?"
- - Spock and Kirk
- Story outline by Don Ingalls: 29 August 1966
- Revised story outline: 12 September 1966
- Second revised story outline: 14 September 1966
- First draft teleplay by Ingalls: 14 October 1966
- Second draft teleplay: 7 November 1966
- Final draft teleplay by Gene L. Coon or Steven W. Carabatsos: 11 November 1966
- Revised final draft teleplay by Coon: 14 November 1966
- Additional revisions: 15 November 1966, 16 November 1966, 18 November 1966
- Filmed: 16 November 1966 – 25 November 1966
- Day 1 – 16 November 1966, Wednesday – Desilu Stage 9: Int. Bridge
- Day 2 – 17 November 1966, Thursday – Desilu Stage 9: Int. Bridge,Sickbay, Transporter room
- Day 3 – 18 November 1966, Friday – Desilu Stage 9: Int. Bridge, Corridors
- Day 4 – 21 November 1966, Monday – Desilu Stage 9: Int. Dilithium recharging section, Recreation room (redress of Briefing room), Sickbay
- Day 5 – 22 November 1966, Tuesday – Vasquez Rocks: Ext. Planet surface
- Day 6 – 23 November 1966, Wednesday – Vasquez Rocks: Ext. Planet surface
- Day 7 – 25 November 1966, Friday – Desilu Stage 10: Ext. Planet surface
- Original broadcast date: 30 March 1967, postponed from 2 February 1967
- First UK airdate: 6 December 1969
- The original script called for a romantic entanglement between Charlene Masters and Lazarus that was eventually cut due to Roddenberry considering it too similar to the romance between Khan and McGivers in "Space Seed". As stated by Roddenberry in a Season One memo: "In both 'Space Seed' and this story, we have a crew woman madly in love with a brawny guest star and flipping our whole gang into a real mess because she is in love… do they have to do [this] in two of our scripts?" 
Cast and characters
- James Doohan (Scott) and George Takei (Sulu) do not appear in this episode.
- This was the second episode that Leslie was seen in the command chair, and the first episode in which Eddie Paskey is credited in the ending credits, albeit as "Lesley".
- Although it is unknown why he got to sit in the command chair, since the navigator in this scene held the rank of lieutenant commander, which means he out ranked Leslie.
- Richard Derr, who plays Commodore Barstow in this episode, later played Admiral Fitzgerald in the episode "The Mark of Gideon".
- Actor John Drew Barrymore (father of actress Drew Barrymore) was originally contracted to play Lazarus, but didn't show up to work when filming began on 16 November 1966. The grievance filed against him on this account by the Star Trek production team led to him being unable to obtain acting work for six months in 1967. Robert Brown was a last-minute replacement. (Inside Star Trek: The Real Story)
- After Barrymore failed to show up on the set, director Gerd Oswald decided to shoot scenes which didn't involve his character. On the second day, it was decided to either shut down production and scrap the episode overall or find a replacement. Robert Brown was literally dragged in to the set, right after he agreed to play the role. He recounted the filming to be very tight and tense. 
- There is no officer played by Larry Riddle as noted in the Star Trek Concordance (citation needed • edit). Lieutenant Larry Riddle was Charlene Masters' jealous boyfriend in the first draft of the script. 
Sets and props
- Part of the dilithium energizer panel uses the same controls as the neural neutralizer from "Dagger of the Mind".
- The dome of Lazarus' time ship was later reused to encase the Providers in "The Gamesters of Triskelion".
- This episode introduces a new set, a small subsection of engineering, described in the final draft of the script, dated 11 November 1966, as the "Lithium [sic] Crystal Recharging Section", which was described as "A portion of Engineering where there are bins into which dilithium crystals are placed for recharging."
- Along with "Friday's Child", this is one of the only two episodes where outdoor planet scenes were filmed both on Desilu Stage 10 and on location (both times at Vasquez Rocks). Originally, all planet-side scenes were scheduled to be filmed on location, but due to the turmoil during production, director Gerd Oswald couldn't finish shooting at Vasquez. Matt Jefferies and the art department prepared a spot on Stage 10 which could accommodate the missing "alternate universe" sequence. 
- Although Lazarus's spacecraft resembles a flying saucer, James Blish describes it as "cone-shaped" in his novelization of the episode in Star Trek 10.
Costumes and make-up
- Periodically throughout the episode, the two versions of Lazarus exchange places. One of them has a wound or bandage on his head which McCoy treated: this is the "insane" Lazarus from our universe; the other is his rational counterpart from the antimatter universe.
- Although Masters is referred to as a lieutenant and works in engineering, she wears a blue uniform of the sciences section, and it has no rank stripes, which normally denotes the rank of Ensign.
- Lazarus' costume was later worn by an extra playing a Babel Conference delegate in "Journey to Babel".
- The visual of the iron-silica planet from orbit is reused footage previously representing Alfa 177 in "The Enemy Within" and M-113 in "The Man Trap". This planet effect was reused again as Argus X in "Obsession" and Ardana in "The Cloud Minders".
- The footage of the two Lazaruses fighting was created by filming two stuntmen fighting in a smoke-filled room with orange and purple walls, then double-exposing its color negative footage over an astronomical photograph of the Trifid Nebula.
- A still image in the closing credits of "The Squire of Gothos" shows the corridor between universes set unaltered by the effects and double exposure. Titled at a 45 degree angle, Shatner stands ankle deep in smoke in a near pose of the crucifixion, falling back into a purple corridor, where an orange line draws the horizon to a vanishing point.
- Unique to the original series are the angle of the Enterprise as it fires its phasers to destroy Lazarus's ship, as well as the use of a single phaser beam and the lack of a sound effect when the beam is viewed from space.
- This is the first time that live two-way communication with Starfleet Command is depicted. In previous episodes, communication with Starfleet Command was through delayed radio messages.
- Depending on which version of this episode you watch, the closing stills change. The original syndicated version and the VHS version show the still as the Enterprise leaving the Earth-like planet from "Miri", however, the Sci-fi Channel and DVD version show the still as just a blue planet, possibly Rigel 12 from "Mudd's Women" or Starbase 11 from "Court Martial".
- The Agony Booth website included this episode among "The Worst of Trek". In their recap, they write that in the episode, "Very little actually happens, and what little that does comes about only because Kirk and Company are written to act in such a way that can only be described as severely brain damaged." The reviewer continues, "I never thought I'd say this, but this episode is making "Spock's Brain" look pretty goddamn good right about now!" He concludes, "this is one of the most poorly constructed fifty minutes I've ever seen. An almost impossibly incoherent script, a damp squib of a finale, and some horrible editing make this one of the true stinkers in the Trek universe." Also, he mentions that "[John Drew] Barrymore didn't show up for filming. Given the script, I can't say I blame the fellow. The rest of the cast should have done the same thing, to be perfectly frank." 
"The Alternative Factor" was the forty-ninth episode of the remastered version of The Original Series to air. It premiered in syndication on the weekend of 1 December 2007 and aside from the standard CGI replacement footage of the Enterprise and the planet-of-the-week, this episode also featured several new, modest effects shots of the alternative warp effect, as well as phaser and transporter effects.
- The next remastered episode to air was "The Return of the Archons".
Video and DVD releases
- Original US Betamax release: 1985
- UK VHS release (two-episode tapes, CIC Video): Volume 11, catalog number VHR 2295, release date unknown
- US VHS release: 15 April 1994
- UK re-release (three-episode tapes, CIC Video): Volume 1.7, 4 November 1996
- Original US DVD release (single-disc): Volume 10, 21 March 2000
- As part of the TOS Season 1 DVD collection
- As part of the TOS Season 1 HD DVD collection
- As part of the Star Trek: Fan Collective - Alternate Realities collection
- As part of the TOS Season 1 Blu-ray collection
Links and references
- Nichelle Nichols as Uhura
- Richard Derr as Barstow
- Arch Whiting as the assistant engineer
- Christian Patrick as a transporter chief
- Eddie Paskey as Lesley [sic]
- William Blackburn as Hadley
- Vince Calenti as Security lieutenant/technician
- Frank da Vinci as Brent
- Tom Lupo as a security guard
- Ron Veto as Harrison
- Unknown performers as
- Bill Catching as Brown's stunt double #2
- Gary Combs as Shatner's stunt double
- Al Wyatt as Brown's stunt double #1
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- "The Alternative Factor" at StarTrek.com, the official Star Trek website
- "The Alternative Factor" at Memory Beta, the wiki for licensed Star Trek works
- "The Alternative Factor" at Wikipedia
- "The Alternative Factor" at MissionLogPodcast.com, a Roddenberry Star Trek podcast
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