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Star Trek: The Alternative Factor

After a dimensional disruption shakes the known galaxy to its very core, the Enterprise is sent to investigate the planet of origin and find a man named Lazarus who claims ignorance. But Lazarus displays strange personality shifts from good to evil and it soon becomes clear that Kirk is not dealing with just one Lazarus... but two. And the second one is a psychopathic killer who means to destroy everything to eliminate his counterpart.

Episode Info

Episode number: 1x27
Production Number: 6149-20
Airdate: Thursday March 30th, 1967

Director: Gerd Oswald
Writer: Don Ingalls

  • Currently 4/10
4/10 (3 Votes cast)
Starring Roles
DeForest Kelley
As Dr. Leonard Horatio "Bones" McCoy
Nichelle Nichols
As Lt. Nyota Uhura

Guest Stars
Janet MacLachlan
As Lt. Charlene Masters

Co-Guest Stars
Richard Derr
As Barstow
Eddie Paskey
As Lt. Leslie
Arch Whiting
As Assistant Engineer
Christian Patrick
As Transporter Chief

Bill Catching
As Anti-Matter Lazarus Being #2
Frank Da Vinci
As Crew Stuntman #1
Gary Combs
As Capt. Kirk's Stunt Double
Ron Veto
As Security Guard #1
Tom Lupo
As Security Guard #2
Tom Steele
As Crew Stuntman #3
William Blackburn
As Security Guard #4
Al Wyatt
As Anti-Matter Lazarus Being #1
Carey Foster (1)
As Crew Stuntman #2
Larry Riddle
As Officer
Vince Calenti
As Security Guard #3
Main Cast
William Shatner
As Captain James Tiberius Kirk
Leonard Nimoy
As Commander Spock


The Enterprise is on a routine patrol exploring a dead Class M world when suddenly the universe “blinks” around them, twice. Spock is at a loss to explain the experience but says it was as if the universe ceased to exist for a split second. They then detect a lifeform on the dead planet below and Kirk takes down a security team. They find a small alien ship and then spot a beard who rants about a Beast that is trying to kill him and destroy everyone. He falls down a cliff face and Kirk has him beamed up to the ship for treatment...

Read the full recap
Episode Quotes
Kirk: What was that?
Spock: What my instruments read is totally unbelievable, Captain. Twice, for a split second each time, everything within range of our instruments seemed on the verge of winking out.
Kirk: I want facts, not poetry.

Lazarus: Why do you give credence to this man?
Spock: I fail to comprehend your indignation, sir. I've simply made the logical deduction that you are a liar.

McCoy: As we both know, I'm a bright young medic with a miraculous touch.

Kirk: Where is he?
McCoy: I don't know, Jim. This is a big ship. I'm just a country doctor.

Kirk: Sometimes pain can drive a man harder than pleasure.

Spock: Jim, madness has no purpose. Or reason. But it may have a goal.

Kirk: So you're the terrible thing, the murdering monster, the creature?
Lazarus: Yes, Captain. Or he is. It depends on your point of view, doesn't it?

Spock: And what of Lazarus?
Kirk: And what of Lazarus?

Episode Goofs
Robert Brown's false beard varies considerably in length and thickness throughout the episode.

Lt. Masters doesn't wear lieutenant braids, and is wearing a blue uniform despite the fact she works in Engineering.

Why does the "good" Lazarus have to sacrifice his life at all? All Kirk needs to do is beam up the bad Lazarus, destroy his ship, and lock him up somewhere so he never recreates it.

What Changed in the Remastered Version
General improvements cited on the main series page. The planet receives a significant visual upgrade with landmarks visible from orbit and new orbital shots of the Enterprise are included. The phaser effect that destroys Lazarus' ship at the end is touched up.

Other Episode Crew

CreatorGene Roddenberry
Executive ProducerGene Roddenberry
ProducerGene L. Coon
CastingJoseph D'Agosta
Costume DesignerWilliam Ware Theiss
Make-upFred B. Phillips
GripGeorge Rader
Property MasterIrving A. Feinberg
Script SupervisorGeorge A. Rutter
GafferGeorge H. Merhoff
OtherHerbert F. Solow (Executive in Charge of Production)
Sound MixerDoug Grindstaff
Special EffectsJames Rugg
Main Title ThemeAlexander Courage
Warning: Star Trek season 1 episode 27 guide may contain spoilers
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