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Star Trek The Original Series Rewatch: “Tomorrow is Yesterday”


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Star Trek The Original Series Rewatch: “Tomorrow is Yesterday”


Published on August 5, 2015

Star Trek, the original series, Tomorrow is Yesterday

“Tomorrow is Yesterday”
Written by D.C. Fontana
Directed by Michael O’Herlihy
Season 1, Episodes 21
Production episode 6149-21
Original air date: January 26, 1967
Stardate: 3113.2

Captain’s log. We open at an Air Force Base in 1969, which picks up a giant aircraft like nothing they’ve ever seen before, and it just appeared out of nowhere, “like it dropped out of the sky.” A plane is scrambled to get a better look, and we see that it’s the Enterprise. They collided with a black hole (they call it a “black star”) while en route to Starbase 9, and wound up at Earth. Scotty manages to get power back online, but warp drive is offline. Sulu reports that the impulse drive is sluggish, but he gets them some altitude. Uhura reports silence on the usual Starfleet channels—all she’s able to get is radio, including an announcement of the upcoming first moon landing. This confirms Spock’s hypothesis that the black star sent them back in time to the 20th century.

The pilot sent to investigate, Captain John Christopher, pursues, getting close enough to see the Enterprise. He’s ordered to bring down the UFO. Uhura picks up the conversation between Christopher and the base, and Spock expresses a concern that the plane can do damage to the Enterprise in its current state. Kirk has Scotty put the plane in a tractor beam, but the aircraft is too fragile and starts to break up. Kirk has Christopher beamed on board. The captain is surprised that they speak English, and offers only name, rank, and serial number.

Star Trek, the original series, Tomorrow is Yesterday

Christopher is angry and confused, and Kirk goes ahead and tells the truth: they’re from the future. Given the evidence, Christopher can’t help but believe him—especially after he meets Spock…

While Uhura shows Christopher around the bridge, Spock reports that they’re in a high orbit with deflectors working, so the locals won’t pick them up on their radar anymore. He’s also concerned about Christopher, as he now has knowledge of the future, which could change history. Kirk orders the quartermaster to provide Christopher with more suitable clothes and then meet him and Spock in the captain’s quarters.

Star Trek, the original series, Tomorrow is Yesterday

Christopher arrives wearing a lieutenant’s uniform (which fits, as the Air Force rank of captain is equivalent to the Navy rank of lieutenant, and Starfleet uses Navy ranks) as Kirk is recording a log entry, and then explains to Christopher that they can’t send him back. Christopher points out that his disappearance would also change history, but Spock has checked—there is no relevant contribution by John Christopher in their history tapes. (Tapes!) Christopher points out that he’s duty bound to report what he’s seen, a problem Kirk can sympathize with, and he has a wife and two kids down on Earth. But Kirk can’t take the risk.

Scotty then reports that repairs should be completed in four hours—but that leaves them with nowhere to actually go. Christopher may not be able to go home, but neither can Kirk and his crew.

Star Trek, the original series, Tomorrow is Yesterday

Christopher has free run of the ship, which proves to be a mistake, as Kirk notices that he’s not in his quarters and puts the ship on security alert. Christopher takes down a security guard, steals a phaser, and tries to convince Transporter Chief Kyle to beam him down. But Kirk shows up and punches him in a manly manner, sending him to sickbay unconscious.

Spock reveals that he didn’t make a thorough enough search: Christopher didn’t make any relevant contributions, but his son will. This rather surprises Christopher, as he doesn’t have a son—at least not yet. So they have to return him, or alter history forever. The other issue is the fact that Christopher activated his wing cameras when he came in visual range of the Enterprise, and Air Defense Command will have made recordings of all his transmissions. Those need to be destroyed, as the wreckage of Christopher’s aircraft (and the lack of a body), as well as the recorded evidence will point to a spacecraft, seemingly of alien design, definitely destructive.

Star Trek, the original series, Tomorrow is Yesterday

Christopher is willing to help, even though it will make his flight out to be the latest in a long line of UFO sightings with no evidence to back it up. He was stationed at the base, and knows the layout, and he sketches it for them, and tells them where to go to find what they need.

Kirk and Sulu beam down, briefly amused by the primitive cork bulletin board. They use a doodad to open the locked door to the records room. As they’re sabotaging the computer, a sergeant catches them and takes their belts. He looks at one communicator and activates the emergency signal, which causes Kyle to beam the sergeant up to the Enterprise. At least they still have one communicator and their phasers. Kirk orders the sergeant kept in the transporter room (which works nicely, as the guard is scared shitless and hasn’t budged).

Star Trek, the original series, Tomorrow is Yesterday

After taking all the computer tapes, Kirk and Sulu go after the film. They find the film in the darkroom. Kirk goes to check the files and finds three officers who are following up the alarm that they didn’t realize they’d tripped. Kirk takes on all three of them, but eventually is taken prisoner. Luckily, Sulu heard the fight, knew it was meant as a delaying action so he could beam back aboard, and he did so, with all the evidence. The problem is, Kirk doesn’t have a communicator, so they can’t distinguish him from all the other humans wandering around the base, so they can’t locate him to beam him back.

Kirk is interrogated by Lt. Colonel Fellini, which pretty much goes nowhere, since the colonel won’t believe the truth and anything else would be a lie.

Star Trek, the original series, Tomorrow is Yesterday

Christopher knows where they’re holding Kirk, but he’ll only provide the coordinates if he goes down with him. Spock, Sulu, and Christopher beam down—only Spock and Sulu are armed—while the sergeant looks on in shock. He’s even more shocked when Kyle activates the food slot and gives the sergeant some chicken soup.

The landing party effects a rescue, and then Christopher takes the gun of the airman Spock subdued and holds it on the Enterprise crew. However, Spock doubles back and sneaks up on Christopher from behind.

Star Trek, the original series, Tomorrow is Yesterday

Spock and Scotty know of a theory that would enable them to travel in time by slingshotting around the sun. It’s risky, but it’s their only shot. The initial shot will send them back in time a bit, which is when they will beam Christopher and the sergeant back.

They head toward the sun. Christopher is overwhelmed—he didn’t qualify for the space program—but Kirk smiles and says to take a look around: he got there ahead of everyone else.

Star Trek, the original series, Tomorrow is Yesterday

Christopher goes to the transporter room. The Enterprise accelerates toward the sun, they hit the breakaway point, and zoom around the sun. They beam Christopher back into his aircraft right at the point where he saw the Enterprise, and now he sees nothing. Uhura picks up his transmissions, confirming that they’re chalking it up as another UFO. They then beam the sergeant back just before he would have broken in on Sulu and Kirk and he sees nothing.

The Enterprise continues forward in time, and then Scotty hits the brakes. Uhura picks up a message from Starfleet Control, and all is well.

Star Trek, the original series, Tomorrow is Yesterday

Can’t we just reverse the polarity? The Enterprise computers were recently overhauled at Cygnet XIV, a female-dominated planet, and they felt the computer lacked personality, so they gave it an amorous, giggly female personality. Spock’s disdain and Kirk’s annoyance provide Christopher with amusement—I guess it’s funny that the future is just as sexist as 1969…

Fascinating. Both Christopher and the sergeant are seriously weirded out by Spock, though Christopher gets over it eventually, to the point where he’s actually engaged in bitter banter with Spock on the subject of trust.

Star Trek, the original series, Tomorrow is Yesterday

I’m a doctor not an escalator. McCoy has a serious discussion with Kirk on the subject of both the possibility of Christopher being stuck in the 23rd century and the Enterprise crew being stuck in the 20th. He also gets great amusement out of Spock admitting to being in error.

Ahead warp one, aye. Sulu does most of the sabotaging, engages in some quick thinking by beaming out the darkroom while Kirk indulges in fisticuffs, and works with Christopher and Spock to rescue Kirk. As an added bonus, he flies the ship during the time jump.

Star Trek, the original series, Tomorrow is Yesterday

I cannot change the laws of physics! Scotty works with Spock on the slingshot, and repeatedly cautions against everything that could possibly go wrong. 

Hailing frequencies open. Uhura is the first one to figure out that something’s amiss when she picks up radio broadcasts.

Star Trek, the original series, Tomorrow is Yesterday

Go put on a red shirt. Security is so good at their jobs that they utterly fail to keep Christopher from going to the transporter room. One guard even gets kayo’d, and his phaser taken by Christopher. It’s left to Kirk to take care of it…

Channel open. “All right, Colonel, the truth is, I’m a little green man from Alpha Centauri, it’s a beautiful place, you should see it.”

“I am going to lock you up for two hundred years.”

“That ought to be just about right.”

Kirk being interrogated by Fellini.

Star Trek, the original series, Tomorrow is Yesterday

Welcome aboard. Roger Perry plays Christopher (he’s credited incorrectly as “Major Christopher”), Hal Lynch plays the sergeant, Richard Merrifield and Mark Dempsey play the Air Force personnel who first discover the Enterprise, and the great character actor Ed Peck plays Fellini.

Plus there’s recurring regulars DeForest Kelley, George Takei, James Doohan, Nichelle Nichols, and, making his first appearance, John Winston as Transporter Chief Kyle.

Star Trek, the original series, Tomorrow is Yesterday

Trivial matters: This is the first solo writing credit for D.C. Fontana, after scripting “Charlie X” off of Gene Roddenberry’s story, who would go on to become one of the most important and influential writers in Trek history. She’d become a script editor on this show, and also work on the animated series, help develop The Next Generation, and write for both TNG and DS9, as well as several novels, comic books, videogames, and episodes of fan films. (Robert H. Justman, in his and Herbert Solow’s book Inside Star Trek: The Real Story, reveal that he came up with the story idea and gave it to Fontana to write, but he was not credited.)

The script accurately predicted that the first moon landing would occur two-and-a-half years hence in 1969.

The original intent was for this episode to follow “The Naked Time,” with the cold restart of the engines causing the Enterprise to go back to 1969, but production schedules and air date shuffling made this pretty much impossible.

Star Trek, the original series, Tomorrow is Yesterday

Twice more, the Enterprise will use the slingshot to travel in time, first in “Assignment: Earth” to do research, and again in Star Trek IV: The Voyage Home to find some humpback whales to bring to the future and save Earth. It’ll also be seen in various bits of tie-in fiction, including Engines of Destiny by Gene DeWeese and the New Frontier comic book Double Time by Peter David and Mike Collins.

Dayton Ward’s short story “The Aliens are Coming!” in Strange New Worlds III and novel From History’s Shadow would provide the aftermath of this story, as Christopher is debriefed by Wainwright, one of the officers who encountered Quark, Rom, and Nog in 1947 Roswell in DS9‘s “Little Green Men.” Shaun Geoffrey Christopher, the captain’s as-yet-unborn son, appears in Greg Cox’s The Eugenics Wars: The Rise and Fall of Khan Noonien Singh and The Rings of Time. Gary Seven, whom we’ll meet in “Assignment: Earth,” also played a background role in the events of this episode, as seen in issue #2 of the Assignment: Earth comic book miniseries by John Byrne.

The day after this episode was aired, the Apollo 1 tragedy occurred, taking the lives of Gus Grissom, Ed White, and Roger Chaffee.

Star Trek, the original series, Tomorrow is Yesterday

This episode establishes that there are twelve Constitution-class ships.

The term “black hole” would not be coined until later the same year that this episode first aired, by physicist John Archibald Wheeler in a speech to NASA.

To boldly go. “Thanks for the look ahead.” Star Trek‘s first real time travel story—though far from its last—is quite an enjoyable tale, although the logic of the ending doesn’t hold together at all. Seriously, how does it make any sense that going back a bit in time and somehow replacing people with the transporter will make them forget everything that happened? Or make it not happen. Or something.

Star Trek, the original series, Tomorrow is Yesterday

But prior to that, it’s a very entertaining episode. A lot of it is on the back of Roger Perry, who imbues Christopher with a distinct personality, and D.C. Fontana’s script, which not only gives Christopher credit for being an intelligent person, but also does a nice job of showing that just because humans have better technology doesn’t mean they’re perfect. (Though the “female personality” computer subplot is pathetic and embarrassing even before you realize that it was written by a woman.) I like the fact that the crew screws up, starting with using the tractor beam on Christopher’s plane, and going on to beaming the sergeant up, not to mention Spock’s incomplete research. I also like how smug Christopher is when pointing it out.

Having said that, the crew doesn’t get caught up in their screw-ups, but move quickly to fix them, from their plan to remove the evidence to Sulu’s quick thinking in beaming back from the darkroom to the slingshot—which we’ll see again. The episode has a good balance of serious danger—the notion of being trapped in the 20th century is a powerful one—and humor—from McCoy’s snark to Hal Lynch’s superb comic work as the befuddled sergeant to Fellini’s interrogation of Kirk.

Star Trek, the original series, Tomorrow is Yesterday

Overall, a good time travel story with a strong guest star. Many time-travel clichés grew out of this episode, but the episode itself is a good one.


Warp factor rating: 8 

Next week:The Return of the Archons

Rewatcher’s note: We’re in the home stretch for a very nifty Kickstarter for a superhero flipbook anthology called The Side of Good/The Side of Evil, for which your humble rewatcher will be writing a Super City Police Department story, and which will also have a new Furious story by Bryan J.L. Glass, as well as tales by Star Trek fictioneers Peter David, Aaron Rosenberg, and Robert Greenberger, as well as Jennifer K. Spendlove, James Chambers, Gail Z. Martin, John L. French, James M. Ward, Neal Levin, and Kathleen O. David. The anthology will be edited by veteran anthologist Danielle Ackley-McPhail and Between Books‘s Greg Schauer, and there are tons of nifty rewards, including bonus fiction and a chance to be a character in one of the stories. Please lend your support!

Keith R.A. DeCandido will be at Shore Leave 37 this weekend at the Hunt Valley Inn in Cockeysville, Maryland, along with actors John Barrowman, David Nykl, Jaime Murray, Tony Curran, Jesse Rath, Rekha Sharma, Daniel Davis, and Roger Cross; fellow Trek novelists Christopher L. Bennett, Kirsten Beyer, Peter David, Kevin Dilmore, Michael Jan Friedman, Dave Galanter, Robert Greenberger; David Mack, John Jackson Miller, Scott Pearson, Dayton Ward, and Howard Weinstein; fellow Stargate novelists Amy Griswold and Melissa Scott; and tons and tons more too numerous to list here. Keith’s schedule can be found here.

About the Author

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Keith R.A. DeCandido


Keith R.A. DeCandido has been writing about popular culture for this site since 2011, primarily but not exclusively writing about Star Trek and screen adaptations of superhero comics. He is also the author of more than 60 novels, more than 100 short stories, and around 50 comic books, both in a variety of licensed universes from Alien to Zorro, as well as in worlds of his own creation. Read his blog, follow him on Facebook, The Site Formerly Known As Twitter, Instagram, Threads, and Blue Sky, and follow him on YouTube and Patreon.
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