Star Trek (1966–1969)
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The Doomsday Machine 

The USS Enterprise encounters the wrecked USS Constellation and its distraught commodore who's determined to stop the giant planet-destroying robot ship that killed his crew.


Marc Daniels


Gene Roddenberry (created by), Norman Spinrad

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Episode complete credited cast:
William Shatner ... Capt. Kirk
Leonard Nimoy ... Mr. Spock
DeForest Kelley ... Dr. McCoy
William Windom ... Commodore Decker
James Doohan ... Scott
George Takei ... Sulu
Elizabeth Rogers ... Lt. Palmer
John Winston John Winston ... Lt. Kyle
Richard Compton Richard Compton ... Washburn
John Copage John Copage ... Elliott
Tim Burns Tim Burns ... Russ
Jerry Catron ... Montgomery


The U.S.S. Constellation and its crew were destroyed by a giant robot ship which consumes planets for fuel, leaving only a guilt-ridden Commodore Decker aboard the crippled ship. Kirk beams over to begin repairs while Decker beams aboard the Enterprise. After Kirk loses radio contact with the Enterprise, the obsessed Commodore seizes command of the starship, determined to destroy the planet-killer, even at the cost of Kirk's ship and the entire crew. Written by

Plot Summary | Plot Synopsis


TV-PG | See all certifications »


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Release Date:

20 October 1967 (USA) See more »

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Did You Know?


The trident scanner Scott pulls out of the new storage area near the doorway to engineering is the same prop Spock uses in Star Trek: Metamorphosis (1967) as he works on the shuttlecraft, and which Ensign Harper uses to plug in the M-5 multitronic unit in Star Trek: The Ultimate Computer (1968). It is identified in The Making of Star Trek as a "Ray Generator and Energy Neutralizer (Spock-Built)." See more »


As the Enterprise (under Decker's command) is being drawn into the planet killer, the actors on the bridge can be seen reacting to a "whining sound" that was specified in the script, but ultimately not used. See more »


Capt. Kirk: Bones, you ever hear of a doomsday machine?
Dr. McCoy: No, I'm a doctor, not a mechanic.
See more »

Alternate Versions

In a version with the updated CGI run on MyNetworkTV, the back-and-forth dialog where Spock says "Vulcans never bluff" is omitted. The sequence jumps from Spock's line, "You *are* relieved" to Decker saying, "Very well, Mister Spock." See more »


Featured in For the Love of Spock (2016) See more »

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User Reviews

Remastered Doomsday Machine: Amazing Star Trek Episode That Can Stand Up to Anything Produced in SF Today Thanks to CGI
26 December 2009 | by classicalsteveSee all my reviews

If there was any Star Trek episode from the original 1960's series that would benefit from a CGI face-lift in the special effects department, it was "The Doomsday Machine". And now the hope has become a reality thanks to the new so-called "Remastered" editions of the series.

The primary shortcoming between the original Star Trek series of the 1960's versus newly produced film and television Science Fiction, such as Star Trek: The New Generation/Voyager, Babylon 5, Independence Day, Star Wars, and countless others, have been the special effects. The visual effects of the original series could never top the CGI effects achieved today. But now this shortcoming has been eliminated with the Star Trek Remastered series; all of the exceptional Star Trek episodes can be viewed as if being seen for the first time with effects that match any SF being produced today. And with the enjoyment of the acting, the story, the characters, and the dialog that made the original Star Trek not only the best SF series of all time but one of the greatest shows ever produced for television, the experience is a wonder to behold.

Overall the story and the acting of the original Star Trek's best episodes surpass most of the writing in typical SF produced in the 1990's and 2000's, and far more compelling than most of the spin-off series. The characters played by William Shatner, Leonard Nimoy and DeForest Kelley still rank as one of the best character-actor combinations of any Star Trek series, and certainly of any SF series to grace the small or large screen. Although Shatner was probably the weakest of the three, the sensibility he brought to Kirk meshed well with his other leads, Nimoy as Spock and Kelley as "Bones" McCoy, who were without a doubt the strongest actors of the series and balanced-out the team.

The Remastered Doomsday Machine is a case in point. "Doomsday" is one of the best-written and best-acted segments of any Star Trek series, be it original or spin-off. Norman Spinrad's compelling tale chronicles the USS Enterprise discovering a wrecked federation starship among space debris, the Constellation. (The original was unable to show any of the debris, and the wrecked ship looked like a small white plastic model.) The ship's demise was at the hands of a giant space weapon characterized as "the devil...straight out of hell" according to Commodore Decker, the last man aboard. As frightening as the Doomsday Machine was as shown in the original 1960's offering, the new Doomsday Machine as presented via CGI is a horrific wonder to behold; a behemoth the length of the Great Wall of China with a maw the size of Mt Everest that could swallow "a dozen starships". The artists that created the imagery did a tremendous job in maintaining the relative proportional sizes of the Doomsday Machine with the Enterprise and the smaller USS Constellation. At one point, the Enterprise appears the size of a flea as compared to the massive Doomsday Machine.

Part of the compelling nature of Doomsday is not just the monstrous "villain" itself, but also the intense dynamism between the characters in which Commodore Decker (William Windom, in one of the best guest performances of any Star Trek episode) attempts to take over command of the Enterprise to combat the machine. Kirk, Mr Scott, and a handful of technicians are left stranded aboard the wrecked Constellation. When Kirk realizes Decker is jeopardizing the safety of the Enterprise to combat the nearly-invincible Doomsday Machine, he is horrified but unable to intervene, or can he? Kirk and Mr Scott work furiously to bring the Constellation back to life...

On a melancholy note, James Doohan (Scotty), whose favorite ST Episode was "Doomsday" did not live to see the new remastered version. But I am certain he would have approved. All of the scenes with the actors are untouched and unchanged. In additions, some references in the dialog that indicate what's happening in space are shown with the CGI that were not present before. For example, after Kirk boards the Constellation and finds Decker, Kirk offers to tow the wrecked ship. The Enterprise is then shown towing the Constellation, which was never seen in the original episode. If you thought the original was good, the new remastered version is superb, and keeping with the spirit of the original. And when the Doomsday Machine makes its appearance, its design is fully based on the original, just a hell of a lot more terrifying! A tremendous Star Trek experience by any standard.

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