In the Futurama episode “Roswell That Ends Well,” Professor Hubert J. Farnsworth (Billy West) offers essential advice about time travel. “Don’t do anything that affects anything,” Farnsworth says. “Unless it turns out you were supposed to do it. In which case: for the love of god, don’t not do it!” 

When it comes to stable temporal loops, you want to follow the last part of that advice. Otherwise, you might create an irresolvable temporal paradox! Here are eight stable time loops from video games, novels, TV shows and movies.

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Song of Storms

In The Legend of Zelda: Ocarina of Time, first released on Nintendo 64, Link is the Hero of Time. Thanks to the Master Sword, he can travel seven years into his future. When he returns the sword to the Temple of Time, his consciousness travels back seven years.

Kakariko Village, with its famous windmill, from The Legend of Zelda: Ocarina of Time.

Link arrives at the windmill in Kakariko Village as an adult. The Phonogram Man tells him seven years earlier, a child taught him the “Song of Storms.” Since then, the song has been going “around and around” in his head. He teaches Link the tune. Link then travels back in time seven years and teaches it to the Phonogram Man. As such, the song itself forms a stable temporal loop. 

When Link plays the song, it creates a tempest. This summons rain and makes the windmill spin. The type of song plays into the motif, as well. The “Song of Storms” is a waltz, a dance that takes its name from the German word Walzer, meaning “to roll or revolve.”

Timothy the Time Traveler

Marvel’s Squirrel Girl: The Unbeatable Radio Show follows Doreen Green (Milana Vayntrub) and her friends as they host a superhero call-in advice show. In the second episode, “Spider-Sense Didn’t Even Tingle,” they get a notable call from Timothy the Time Traveler (Scott Aiello). Although they don’t recognize his voice, he acts like he already knows them. He thanks them for telling him to “overload the tachyon inducer by shunting the anti-time plasma feed into the secondary phase coil.”

Squirrel Girl has been sent back in time to a random point in the 60s but its the day before her fight with Doctor Doom! A chart visualizes what this time loop looks like.

This is not Doreen’s first-time travel adventure. From The Unbeatable Squirrel Girl (2015b) #5 by Ryan North, Erica Henderson, Rico Renzi, and Travis Lanham.

Several weeks later, in the penultimate episode of the podcast, Timothy calls again. From Timothy’s perspective, this is earlier on the timeline. He’s panicking about traveling uncontrollably backward in time due to a malfunctioning time machine.

Fortunately, Brain Drain (Peter Hermann) can use his incredible robot abilities to recite the statement Timothy said in episode two. With this knowledge, Timothy can repair the time machine. Thus, he can travel back in time to give the superheroes the information to assist him. 

Kirk’s Eyeglasses

Early in Star Trek II: The Wrath of Khan, Admiral Kirk (William Shatner) gets a birthday gift from Doctor McCoy (DeForest Kelley): a pair of antique eyeglasses. While one lens is broken, Kirk warmly accepts the gift. 

The glasses with the broken lens that McCoy gives Kirk in Star Trek II: The Wrath of Khan, forming the start of a time loop.

Later on in Kirk’s timeline, in Star Trek IV: The Voyage Home, the crew travels back to 1986. To obtain 20th Century currency, Kirk sells the eyeglasses to an antique dealer for a few hundred dollars. Spock (Leonard Nimoy) asks about selling a gift from McCoy. Kirk opines that the beauty of the situation is McCoy will gift him the glasses again. A stable time loop!

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Some may protest that this is not a stable loop, as the glasses will steadily degrade and eventually break. However, when McCoy gifts Kirk the glasses, they have a cracked lens. This was repaired when Kirk sells them in the eighties. This suggests that at some point between the second and third movie, Kirk had them restored using 23rd Century technology. Thanks to this tech, the glasses could have been repaired molecularly. This ensures the loop is infinitely sustainable.

The Complete Works of William Shakespeare

In the Thursday Next novels by Jasper Fforde, the eponymous LiteraTec’s father, Colonel Next, is a member of The Chronoguard. This secret agency is charged with maintaining the integrity of the timeline. But in The Eyre Affair, the Colonel faces a conundrum: who wrote William Shakespeare’s famous plays? Because the playwright doesn’t seem to be all that motivated!

The cover of The Eyre Affair by Jasper Fforde.

Eventually, the Colonel resolves the issue by traveling back to the 17th Century and giving Shakespeare a copy of The Complete Works of William Shakespeare and a timetable for releasing the plays. While the playwright is inspired to write some of his work to accompany the plays brought back in time by Colonel Next, in this timeline, those thirteen plays initially brought back represent a stable time loop.

Universal Time Code

Bender’s Big Score was the straight-to-DVD movie released after Futurama was canceled. A trip to the nude beach planet revealed that the secret to paradox-free time travel, the Universal Time Code, was contained in a tattoo on the butt cheek of Philip J. Fry (West). The Universal Time Code allows paradox-free time travel because it resolves potential issues by ensuring time travel duplicates are quickly killed off.

The subsequent misadventure saw a trio of scamming aliens taking control of Earth thanks to the Universal Time Code. Eventually, Bender (John DiMaggio) can scam the scammers, and Earth is returned to the Earthicans. But after that happens, “way at the end,” Bender must travel back in time and place the tattoo on Fry’s butt.

Bender Bending Rodriguez (John DiMaggio) and his many time travel duplicates in The Beast with a Billion Backs.

This means the Universal Time Code forms a stable temporal loop. Too bad Bender proceeds to convince all of the time travel duplicate Benders hiding down in the Planet Express basement with him to wait until the end to emerge. The ensuing paradoxes cause the fabric of the universe to rip apart, leading to the events of the sequel, The Beast with a Billion Backs.

Chateau Picard Skeleton Key

The second season of Star Trek: Picard saw Jean-Luc (Patrick Stewart) and the crew of the La Sirena traveling back in time to 2024 thanks to some shenanigans undertaken by Q (John de Lancie). We learn of a tragic event from Picard’s past throughout the season.

The event in question, his mother’s death, takes place because the Chateau Picard skeleton key is located in a hidey-hole. In the 21st Century, Picard removes the key. This action could prevent future events from transpiring.

Patrick Stewart as Picard replacing the key in the wall in Chateau Picard.

Photo Cr: Trae Patton/Paramount+ ©2022 ViacomCBS. All Rights Reserved.

In the season finale, “Farewell,” Picard must make a hard choice: does he leave the skeleton key in the hidey-hole, thus accepting the tragic events that will play out in the future? Ultimately, he leaves the key, stabilizing the temporal loop.

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Johnny B. Goode

The first movie in the Back to the Future trilogy follows Marty McFly (Michael J. Fox) as he travels back three decades. He inadvertently encounters his mother (Lea Thompson) and father (Crispin Glover), nearly creating an irresolvable paradox by preventing his birth.

Fortunately, with the assistance of a younger version of the inventor of the time machine, Doc Brown (Christopher Lloyd), Marty is able to restore the timeline and ensure he will be conceived. After this has been accomplished, Marty takes to the stage to play a rendition of “Johnny B. Goode,” originally written and performed by Chuck Berry.

One of the other musicians present at the Enchantment Under the Sea dance as Marty performs is Marvin Berry. Marvin calls his cousin Chuck and holds up the phone. This suggests that, like the “Song of Storms,” the song “Johnny B. Goode” is a stable temporal loop.

The Incident

On LOST, Oceanic 815 crashes on September 22, 2004. In the second season finale, “Live Together, Die Alone,” we learn that the plane crashed because Desmond Hume (Henry Ian Cusick) failed to press the button in the Dharma Initiative hatch known as “The Swan.” This button had to be pressed because of an enigmatic “Incident” occurring sometime in the past.

In the fifth season of LOST, several 815 survivors traveled back in time three decades. After infiltrating the Dharma Initiative, Jack Shepherd (Matthew Fox) takes it upon himself to prevent the future crash of 815. He attempts to do this by detonating Jughead, a hydrogen bomb, at the site where The Swan will eventually be located. He reasons that the Swan will never be constructed by destroying the area, and thus 815 will never crash.

Faraday (Jeremy Davies) examines the hydrogen bomb Jughead on LOST.

But Jack is “Ka-Mai” (ka’s Fool). The detonation of Jughead, which is accomplished thanks to an act of agency by Juliet Burke (Elizabeth Mitchell), is “The Incident.” He was attempting to prevent a tragedy from his past. But Jack himself is responsible for creating the conditions that cause the disaster in the first place.

This article was originally published on 6/11/22.

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