Star Trek Reviews

Return to season list

Star Trek TOS - Season 2 - Episode 06

Star Trek TOS - 2x06 - The Doomsday Machine

Originally Aired: 1967-10-20

A machine that destroys planets threatens the Enterprise. [Blu-ray] [DVD]

My Rating - 10

Fan Rating Average - 5.41

Rate episode?

Rating: 0 1 2 3 4 5 6 7 8 9 10
# Votes: 126 13 12 5 27 56 9 16 32 48 124

Filler Quotient: 2, filler, but an enjoyable episode nevertheless. You can skip this one, but you'd miss out on some fun.
- There's no essential plot or exposition in this episode that renders it unskippable, but it's definitely a fun ride!

- Throughout the episode numerous characters make mention of the planet eating monster devastating all the nearby "solar systems." This is a common error. The term they were looking for is planetary system. The planetary system we live in is called the Solar System because our star is named Sol. As such, the term "Solar System" is a proper noun, not a generic term.

- This episode is a candidate for my "Best Episode of TOS Award."
- Uhura and Chekov are remarkably absent from this episode.
- This episode establishes that detonating a starship impulse engine can generate a 97.835 megaton explosion.
- This episode was nominated for the 1968 Hugo Award for Best Dramatic Presentation.

Remarkable Scenes
- The sight of the crippled vessel Constellation.
- The freaked out commodore Matt Decker.
- The revelation that the entire crew of the Constellation was killed by the planet eating machine.
- McCoy: "I'm a doctor, not a mechanic!" (Count #5 for "I'm a doctor, not a [blah]" style lines McCoy is famous for.)
- Kirk's speculation that the planet eating machine must be a remnant from a distant, ancient war which destroyed its creators.
- Spock's calm and logical refutation of Decker's argument, then doing his duty and giving up command despite the fact that Decker's decision was wrong.
- The Enterprise engaging the planet eating machine.
- Kirk to Decker: "You're the lunatic who's responsible for almost destroying my ship!?"
- Spock taking command.
- Spock: "Vulcans never bluff."
- Decker's battle with the security person.
- Decker plunging himself into the planet eating machine.
- Kirk regarding plunging the Constellation into the planet eating monster: "I'm gonna ram her right down that thing's throat!"
- The Constellation exploding inside the planet eating machine.
- Spock regarding the planet eating machine: "It's quite dead."

My Review
In what is easily the most exciting episode since Balance of Terror, captain Kirk, his crew, and a crazed commodore Decker do battle with an automated weapon from another galaxy programmed solely to seek out new life and new civilizations and destroy the strange new worlds they inhabit. Indeed the planet eating machine featured in this story is in every way the antithesis of our Star Trek heroes and presents itself as a worthy foe to the Federation.

This well paced story delightfully sets up the freak of circumstances that places Decker in temporary command of the Enterprise while Kirk is left to fend for himself on Decker's crippled ship. Likewise the exposition that Decker beamed his entire crew down to a planet that he was tragically unaware the planet eating machine was about to destroy also nicely sets up Decker's despicably unstable demeanor throughout the story.

You can't help but root for Decker during his ill-advised battle with the planet eating machine. A part of you wants his crazy desperation to work. Meanwhile the race against the clock for Kirk to rush in and save his ship using Decker's crippled hulk of a ship is a thrilling ride with an excellent climax. Star Trek sure can do action well when it wants to and the space battle depicting two Federation ships doing battle with the planet eating monster was masterfully choreographed. If only Balance of Terror had this much battle footage!

The way Kirk and Decker counterpoint each other throughout the story is also nicely done with Kirk doing more with less while Decker continues his downward spiral of doing less with more. In the final act it was both touching and clever for Kirk to take inspiration from Decker's suicide move and at the end of the story watching Kirk stare down death wondering if his crew would fix the transporter in time was excellent suspense. Overall an outstanding episode.

The following are comments submitted by my readers.

  • From rhea on 2008-04-27 at 8:50pm:
    Decker as a Commodore: well, that depends. In some fleets on Earth (e.g. in the UK), a Commodore (a flag rank) outranks a Captain, so if this is the case in Starfleet Decker outranks Kirk and can take command of the Enterprise even against Kirk’s direct order. That is however weird since Commodores don’t command single ships on a regular basis. Unless the writers accepted this kind of plot hole for dramatic purposes.
    On the other hand, an American Commodore has the rank of a Captain, but temporarily is given command of a small fleet and is thus temporarily elevated in rank so he outranks the other Captains. The authority attached to the rank is temporary; the person stays a Captain and retains the duties attached to a Captain’s rank. Out of courtesy, however, the title is sometimes still used even after the temporary mission is over, so Decker may well have been a regular Captain who was once elevated to Commodore for a special mission and retained the title from it. What do you think?
  • From TashaFan on 2008-09-19 at 2:24am:
    Decker is a Commodore for dramatic effect. As a Commodore he outranks Kirk and therefore it is clear that when Kirk forces him to relinquish command, it's not a battle of equals, but Decker has been emasculated by his junior. It also means Kirk's actions are not just an argument among peers but are actual insubordination. If Decker was just another Captain there would be much less dramatic conflict. Although I agree with the other comment, in the episode with the M5 computer we see that Commodore Bob Wesley is indeed in command of a fleet of four ships.
  • From Ggen on 2012-03-15 at 11:01pm:
    This was an altogether awesome episode. The central plot and its resolution are both quite good. At the forefront of the entire thing is the twisted psyche of the Commodore, clinging to a failed captaincy, trying to redeem himself in his own bizarre, suicidal way. The Commodore is rather brilliantly written and portrayed and a kind of twisted pleasure to watch. (Interesting how in his misguided efforts he ultimately did help stop the doomsday device by giving Kirk the right idea).

    The command tensionS on the Enterprise between the Commodore, Spock, and McCoy was especially great.

    I have to comment here about the Commodore's fight sequences en route to the shuttlebay, which were absolutely awesome. Something in the choreography was definitely lost, irretrievably lost between the transition from TOS to all the later series. (I just watched TNG The Hunted which is about a supersoldier and has numerous fights, all of them atrocious when compared to TOS...)

    The doomsday machine was an interesting idea (later recycled somewhat in TNG 1x21 Arsenal of Freedom and Voyager 2x17 Dreadnought) and was executed sufficiently well. I can't quite decide whether the model and special effects were silly or awesome (I think some strange mixture of both). The final explosion was definitively cool.

    If the Enterprise was more maneuverable than the doomsday device, it stretches credibility a bit to have it reappear "out of nowhere" and catch everyone by surprise early in the episode. Of course, there was the matter of "subspace interference," but from what I recall, that was mostly discussed in terms of communications, not things like long-range sensors, the viewscreen, etc...
  • From warpfactor 10.1 on 2012-09-20 at 5:20pm:
    I'd forgotten what a great episode this was. I thought it was exciting despite the fact that I knew Kirk wasn't going to die (hope that doesn't spoil it for anyone). The dramatic tension regarding Decker's clash with Spock and Kirk was well done. Guests often get to overact but somehow it doesn't seem out of place and is almost necessary given the relatively short episodes. Although Decker seems as mad as a box of frogs at least he was prepared to go down with his ship which is more than can be said for at least one captain recently.
    I thought the visual effects were done well (being no fan of CGI).
    The one thing stopping me giving it quite as high a score as I might is NO UHURA! There can be no excuse for that. No wonder Scotty was a bit subdued.
  • From Royals42 on 2013-06-12 at 6:22pm:
    Is it just me or is there no thought whatsoever on shooting Photon Torpedos. I know it probably wouldn't have done much but maybe shooting a dozen right up the throat of that thing would have been comparable to the explosion of the ship.

    Other than that it was in my top 5 episodes of TOS. #1 of course is Balance of Terror! It was exciting to see something from another Galaxy and it would have been more interesting if they had examined it more after they "killed it." However maybe it's identity would have made it less menacing.
  • From Scott Hearon on 2014-04-06 at 11:55am:
    Excellent episode. I gave it an 8/10.

    The only things that bug me are: (1) the way that Decker becomes oddly smug and calmly self-satisfied right in the middle of his fit of obsessed vengeance/guilt. It seemed completely out of place. (2) At this point, I'm rather tired of just how insanely quickly Kirk becomes bemused and cracks wise, even immediately after a horribly traumatic experience. I know some hardcore devotees of TOS will consider this blasphemy, but it just rubs me the wrong way.

    All else about this episode is great. The shift of Decker from victim to villain to hero is splendid viewing. The antagonist Doomsday Machine, obviously social commentary about the Cold War arms race, is the most terrifying thing that I've seen in a Star Trek episode. Having Scotty be a major part of defeating it was fun, and the entire 3-way interaction between the Machine, Kirk on the Constellation, and Decker on the Enterprise was perfectly balanced. The drama that ensues moves the tale along at a great pace, and it truly is one of the absolute best episodes.
  • From Chris Long on 2017-11-08 at 9:39pm:
    I know I'm late to this great website so forgive me.

    The acting by the guy who played Decker was superb. The one thing that draws me back to TOS is a generally outstanding acting by the cast and the guest stars!

    The "Don't you think I know that?" line is one of the most heart-wrenching in television in general.

    Contrasted against Kirk's casualness at the end of episodes where billions of people have died, it was pretty stark.

    In agreement with Scott Hearon, I'm constantly annoyed by that little 'habit' of TOS.
  • From Alan Feldman on 2022-06-25 at 6:49pm:
    "Planetary system" suffers from the same bad logic used against "solar system." The argument goes: 'Solar system contains "Sol," and so cannot refer to other solar systems.' Well, planetary system contains "planet," and therefore cannot refer to the planets' sun, the system's meteoroids, asteroids, moons, Kuiper objects, Oort cloud, etc. So "planetary system" suffers from the same logical "error" that "solar system" does. The only reason we even have such a term is the discovery of exoplanets. That was novel. Stars are old hat. So astronomers were studying these newly discovered planets, which obviously make up planetary systems. But a solar system is so much more than a planetary system: Its sun, moons, meteoroids, asteroids, Kuiper objects, etc. But the powers-that-be have already forced upon us this equally, if not more so, defective term. So be it. Again: "Solar system" contains Sol, so it only means ours (contrary to the dictionary). So that means that "planetary system" can only refer to planets, as it contains "planet," and not the rest of the remote solar system. Equally bad logic in both cases.
  • From Alan Feldman on 2022-06-25 at 7:25pm:
    I heartily recommended the original non-CGI version. While there are problems with the special effects, the new version needlessly introduced some serious problems.

    First of all, the machine is basically a flamethrower. Supposed to be pure anti-proton beam, which you could imagine is the case in the original. But in the new version, it's just a flamethrower. A flamethrower! It comes all the way from another galaxy, and it's a flamethrower. Well whoop-dee-do. And when the thing is finally killed, it droops.


    It's out in deep space. There's no up and down in space! There's enough of a problem with gravity almost everywhere, including on a ship with almost no power. And now the thing droops?! This is not an improvement!!! In the original it actually looked dead. Frozen, even. And the explosion that kills it is in some sense better in the original.

    I also think the old one looked scarier with its abstract optical effect at the "bottom" of its "throat." In the new one, it's just some flames.

    Somewhere in the CGI version you can see the nacelles in the viewer. We're talking 200 or 300 years in the future, and they can't have a clear, non-claustrophobic view? Really?

    Yet another problem: What are the horizontal "wrinkles", esp. when the ship is approaching the camera? Looks like some weird form of interlacing. Maybe it's just my copy. If not, so much for "superior image quality."


    As great an episode as this is, it has some problems:

    How the hell did Scotty, immediately upon materializing, know there was a problem with the transporter?

    How did the communications officer get those reports so fast? There is practically no time between her reciting them.

    Why didn't they fire down the throat of the thing? Why didn't the thing blast them when they're right in front of it? OK, maybe the thing wanted to swallow it for "nourishment."

    I think it's in no small part the music that makes this ep so good, despite all its problems. And yes, William Windom puts in an awesome performance. Oh, and as usual, the sound effects are awesome.

    Again, I heartily recommend the original version, even though you can see stars through its "wall" at the front of the machine.

    BTW, I still love this episode. Certainly no. 1 for action, and most importantly as always, a good story.


    Ever notice that the windows in the shuttle craft are too high for the "pilot" to see out of?

Prove to me that you are a real person and not a spam robot by typing in the text of this image:

Return to season list