Original air date: March 8, 1968
Dr. Richard Daystrom (William Marshallnote ), creator of computer systems that ships all over Starfleet use, comes aboard to supervise a test of his new M-5 multitronic computer. The M-5 has been designed to markedly improve the efficiency of vessels in which it's installed, ultimately making their crews obsolete. Most of the Enterprise crew is taken to a nearby Starbase, leaving only a tiny skeleton crew of twenty. Daystrom installs a box with a cut-off switch on Kirk's command chair which will enable him to return the ship to manual control.
M-5 passes the first few tests with flying colors, making a landing party selection that seems better than Kirk's recommendationnote , and operating the ship much more quickly than the crew can during a surprise mock battle with the Lexington. After the defeated Lexington signals "our compliments to the M-5 and Captain Dunsel note , Kirk begins to question whether he really is out of a job. Then M-5 goes out of its way to destroy an un-manned Federation freighter the Enterprise encounters, and Kirk finds that the cutoff switch doesn't work at all. Kirk decides to pull the plug, but M-5 protects itself with a force field and the Red Shirt who tries to unplug it from the ship's power supply in Engineering meets his destiny.
After Spock questions why the computer is not behaving logically, Daystrom reveals that he imprinted his own memory engrams on the M-5, giving it his human instincts and adaptability, but (it turns out) none of his self-control or good sense. Soon the afore-planned wargames start and M-5, in full control of the Enterprise, fatally cripples the Excaliber's life support, killing the ship's entire crew.
The head of the games and Kirk's superior, Commodore Wesley, on the Lexington, is unable to contact Kirk because M-5 is in control of the Enterprise's communications, and assumes that Kirk has gone rogue. He asks Starfleet to give him permission to have his remaining ships fire on the Enterprise with full-strength weapons. In the short time they have before Starfleet responds Daystrom talks to M-5, trying to find out why it did what it did. McCoy warns Kirk that Daystrom is on the verge of a nervous breakdown, knowing that his own creation, modeled on his own thoughts, could kill people when he himself is a sworn pacifist.
Poor Daystrom's psyche begins to unravel, and as he starts to rant to the bridge crew that the M-5 can't and shouldn't be stopped he's treated to a Vulcan neck pinch. Spock advises Kirk to treat M-5 as a person rather than a computer. Kirk asks M-5 to scan the Excaliber for life signs. When M-5 can't detect any he explains to M-5 that what it has done is murder, and that the penalty for murder is death. M-5 agrees and shuts itself down, leaving itself, and the Enterprise, open for attack by the Starfleet squadron.
Commodore Wesley is just about to give orders to destroy the Enterprise when he notices that her shields are down...he knows it may be just a trap but decides to give Kirk a second chance and breaks off the attack. The M-5 is disconnected and disassembled, Daystrom is sent to where he can get some counselling, and the Enterprise goes on its way.
The Ultimate Tropes:
- A Father to His Men: Kirk is enraged and horrified when M5 vaporizes the unfortunate Ensign Harper, and at Daystrom's pathetic excuses.Kirk: "That wasn't a minor difficulty! That wasn't a robot! That thing murdered one of my crewmen, and now you tell me you can't turn it off?!"
- A.I. Is a Crapshoot: The crew of the Enterprise is shocked when the ship is outfitted with the M-5 multitronic unit, a powerful supercomputer created by Richard Daystrom, as a means of replacing humans. Some are curious, but Kirk is highly skeptical. His worries prove true when the ship starts going nuts, going so far as to destroy sister Constitution-class ship U.S.S. Excalibur. After they find out that Daystrom used his brain engrams as a template, Kirk is able to convince the computer that it killed someone and must be punished, causing the computer to shut down.
- And That's Terrible: Daystrom has to tell the M-5 that murder is wrong. Justified, as M-5 is a computer, and computers only know what they're programmed to know, nothing else. Empathy, compassion, and sanctity of life have to be programmed in and apparently Daystrom didnít do a good enough job programming those things in.
- Batman Gambit: Kirk uses one in the end. With the M-5 shut down, he orders Scotty to shut down everything when communications can't be brought up in time. He hopes that Wesley won't attack with everything down. Thankfully, Wesley decides to take the risk and orders the attack force to stand down.
- Bottle Episode: Producer John Meredyth Lucas bought Laurence N. Wolfe's unsolicited teleplay because it could be made fast and cheap, using only the existing Enterprise sets, and decided to direct the episode himself.
- Broken-System Dogmatist: Daystrom slowly becomes this, along with his Sanity Slippage, as he tries to explain away the errors that the M-5 keeps making, until eventually the M-5 starts killing people, and he goes all out A God Am I.
- Brain Uploading: How Daystrom created M-5's AI. Spock sarcastically suggests that Bones do the same thing, predicting that the resulting AI would be completely dysfunctional.
- Cargo Ship: In-Universe between Spock and the M-5.Bones: Did you see the love light in Spock's eyes? The right computer finally came along.
- Catchphrase: Lampshaded after Spock gives his appraisal of Daystrom's behavior re the M-5:Bones: Spock, please do me a favor, and don't say it's "fascinating."
Spock: No, but it is... interesting.
Bones: [rolls eyes]
- Curb-Stomp Battle: The M-5 destroys the Excalibur and seriously damages the Lexington, Hood, and Potemkin within the first few minutes of the war game exercise. Justified, as none of the other ships expected M-5 to use weapons at full strength.
- Cut the Juice:
- How the Enterprise crew tries to take out M-5. Scratch one Red Shirt.
- Later, how Kirk hopes to prevent the Federation battle fleet from destroying the Enterprise since communications are still out.
- Despair Event Horizon: M-5, once Kirk helps it realize what it's done.
- Easily Condemned: After the Enterprise begins attacking the other ships, Wesley assumes awfully quickly that Kirk has gone rogue rather than blame the M-5, which had been in command earlier.
- Facial Dialogue: Through averted gaze, popped eyes, and slight gyrations of the head, we can see pretty clearly during Daystrom's earlier Motive Rant in Engineering, both that Daystrom is starting his Sanity Slippage and that Bones is noticing it. This makes his later assertion that Daystrom is "on the verge of a nervous breakdown, if not complete insanity" fairly easy to determine for ourselves.
- Failsafe Failure: Before the test starts, the Enterprise crew installs an override switch on Kirk's command chair, allowing him to override M-5's control over the ship's systems in case something goes wrong. Naturally, the switch is rendered inactive when M-5 starts going rogue.
- Famous, Famous, Fictional: Daystrom is a recipient of "the Nobel and Zee-Magnees prizes", and Kirk compares him to "Einstein, Kazanga, or Sitar of Vulcan". In each case, the first is real and the rest of the list is fictional.
- Forgets to Eat: At first, it looks like Bones is reminding Kirk to eat when he brings in a covered dish. Turns out, he just figured that Kirk needed a freaking drink after all that happened.
- Friendship Moment: The other two members of the three each try to support their captain and friend as he faces the possibility of losing his ship.
- McCoy:Kirk: To Captain Dunsel.McCoy: To James Kirk, Captain of the Enterprise.
- Spock:Spock: Practical, Captain? Perhaps. But not desirable. Computers make excellent and efficient servants; but I have no wish to serve under them. Captain, a starship also runs on loyalty to one man, and nothing can replace it, or him.
- Future Slang: A "dunsel" is a thing that serves no purpose. Ironically, the character in the (non-canon) continuation novels of Star Trek: Enterprise who was named after the slang term sacrificed himself and his ship to protect other ships, the very opposite of a thing that serves no purpose.
- Glory Days: Daystrom's Freudian Excuse for being so obsessed with the success of the M-5 is that he doesn't want anyone to think that he's a Teen Genius who fizzled out.
- Gut Feeling: Kirk has an uncomfortable sensation that something is wrong about M-5, but he wonders if it's just because he's jealous. It isn't.
- Hope Spot: It looks like Spock and Scotty have successfully cut off the M-5, until Sulu and Chekov find that their controls are still unresponsive.
- Instant A.I.: Just Add Water!: M-5 starts draining power from the Enterprise to be more powerful.
- Jerkass: While not without his good side, Wesley comes off as majorly insensitive because of his witticism while the M-5 is still doing well: "Our compliments to the M-5 unit, and regards to Captain Dunsel. Wesley out." As stated in Future Slang, a "dunsel" is something which serves no useful purpose. Kirk is so stung by hearing it that all he can do is shamble off the bridge without a word, while the rest of the command crew look absolutely disgusted with Wesley's quip. Jeez, Bob, what did Jim ever do to you?
- He's also very quick to assume that Kirk is the one who ordered the attack on the Lexington and the other Starfleet ships, rather than the more reasonable conclusion that the M-5 computer is malfunctioning.
- That said, he does become something of a Jerk with a Heart of Gold at the end, when he refuses to fire on the powerless and vulnerable Enterprise when he has the chance, which Kirk credits to Wesley's sense of humanity.
- Job-Stealing Robot: M-5. Kirk and Bones discuss the history of technology making certain jobs obsolete.
- Logic Bomb: This should just be called The Kirk Maneuver considering how many times Kirk has used this to take out out-of-control computers. In this case, he argues that the M-5 was designed and programmed so that humans wouldn't have to risk themselves in space, and that by murdering the crew of the Excalibur, M-5 has violated its own core programming.
- Ludd Was Right: Kirk does not like the idea of his job being taken over by a computer. Especially when M-5 tags him and McCoy as "non-essential personnel" for a landing party.
- Mama Didn't Raise No Criminal: Daystrom stubbornly refuses to admit that his computer was at fault— he created it, and he's a pacifist, so his machine should not be able to engage in unprovoked aggression.
- Mildly Military: Kirk is in command of the Enterprise at the end of the episode as it flies back from the war game location to the starbase where the rest of the crew was left. If a current US naval vessel so much as dented another during an exercise (let alone effectively destroyed it, like Enterprise did to Excalibur), the captain would be relieved even if it wasn't directly their fault (or, as in Kirk's case, it wasn't remotely his fault at all) pending an investigation to make absolutely fucking certain it wasn't his fault.
- Motive Rant: While M-5 is laconic about its motives, and can be talked to and logically reasoned with by someone a little further away, Daystrom's old insecurity and pain ends up sending him down a different path that gives the actor a hell of a scene to perform.Spock: I am most impressed with the technology, Captain. Doctor Daystrom has created a mirror image of his mind...M-5: ...my consideration of all programming is that we must survive.Dr. Richard Daystrom: We will survive! Nothing can hurt you. I gave you that. You are great, I am great... [starting to lose focus] Twenty years of groping, to prove the things I'd done before were not accidents... seminars and lectures to rows of fools who couldn't begin to understand my systems! [remembering] Colleagues— colleagues laughing behind my back at the Boy Wonder, and becoming famous building on my work. Building on my work!
- My God, What Have I Done?: When forced to confront the fact that it murdered hundreds of people on the ships that it attacked, M-5 shut itself down, leaving itself open to destruction to atone for its crimes.
- No Conservation of Energy: This episode correctly predicts that future computers would draw more power for complex tasks than for simple ones, although tapping into the warp engines seems excessive! What's overlooked, however, is that all that energy ends up as heat. M-5 is drawing vast amounts of power, yet somehow avoids melting into slag.
- One-Liner, Name... One-Liner: When Daystrom starts to realize how far out-of-control the M-5 is during the botched war game.
- Off-the-Shelf FX: The other four starships are AMT plastic model kits.
- Paintball Episode: For the wargames, the phasers on all ships are set at 1% power, with all simulated damage recorded by computer. This then gets defied when M-5 turns the Enterprise's phasers up to full power and cuts loose against Wesley's flotilla.
- Precision F-Strike: At least by the standards of the time:Wesley: Full phasers? What the devil is Kirk doing?!
- Real Award, Fictional Character: Daystrom is cited as a Nobel Prize winner for the invention of duotronic computers.
- Reasonable Authority Figure: Commodore Wesley tries to discover what's gone wrong with Enterprise, and when presented with an opportunity to destroy Kirk's ship, he orders a stand-down because the Enterprise drops her shields and deactivates her weapons.Kirk: I wasn't sure. Any other commander would have simply followed orders and destroyed us, but I knew Bob Wesley. I gambled on his humanity.
- Redshirt: M-5 vaporizes Harper, much to Kirk's horror and rage. Daystrom tries to excuse this by saying "M-5 needed more power... the Ensign merely got in the way". At that, Kirk growls "And how long before we all 'just get in the way'?"
- Red Shirt Army: The crews of the other Constitution-class ships. We only meet Commodore Wesley, and the Excalibur's captain is the only other one given a name (when he dies).
- Religious Robot: Daystrom apparently taught M-5 that murder violated the laws of both Man and God.
- Rotten Robotic Replacement: A computer called the M-5 is installed on the Enterprise to determine if it can replace James Kirk as captain of the ship. M-5 develops artificial intelligence, goes crazy, and tries to destroy four other Federation starships.
- Rules Lawyer: Daystrom is quick to point out when Kirk has to put the M-5 in command, even though Kirk is very reluctant.
- Sanity Slippage: As M-5's murderous misdeeds become more and more impossible to downplay, Dr. Daystrom's attempts to rationalize them drive him over the edge until he is raving hysterically and has to be neck-pinched into submission.
- Say My Name:Kirk: DAYSTROM!!!
- Skewed Priorities: It's symptomatic of just how far round the bend Daystrom has gone that, when he hears that the three other Federation ships are preparing to destroy the Enterprise, his reaction is "They can't do that! They'll destroy the M-5!"
- Stock Footage:
- The space station seen at the beginning of the episode is recycled footage of Deep Space Station K-7 from "The Trouble with Tribbles".
- The SS Woden is recycled footage of the SS Botany Bay taken from "Space Seed".
- The crippled USS Excalibur is recycled footage of the USS Constellation from "The Doomsday Machine".
- A close-up of the three scanning heads on the trident scanner in this episode seem to be a re-use of the disruptor weapons from "A Taste of Armageddon".
- Suicide by Cop: Or in this case, "suicide by Federation Starship". Lucky for our heroes, Commodore Wesley doesn't take the bait.
- Third-Person Person: M-5 always refers to itself as "this unit."
- Thou Shalt Not Kill: One of Daystrom's basic reasons for creating the M-5 was to save human lives, and the difference between self-defense and murder becomes an explicit conversation between a couple of geniuses and a machine that doesn't quite get it here.
- Three Laws-Compliant: M-5 fails the first law spectacularly, though Kirk has to hammer it with the fact that it did commit murder.
- Unseen Prototype: M-1 through M-4.
- Vitriolic Best Buds: Spock and Bones snipe each other at every opportunity.
- Wild Goose Chase: Or, as The Spock puts it, "pursuing a wild goose" is what happens when they try to cut off a circuit that M-5 has already bypassed.