The Cretaceous Is Always Doomed

"We're in Pompeii!... And it's Volcano Day!"

— The Doctor, Doctor Who, "The Fires of Pompeii"

Time Travel is here and it's time to go to the Cretaceous at last and observe some dinosaurs! But we gotta hurry up, because by the end of the day that asteroid is going to hit!

But wait, wasn't the Cretaceous period 79 million years long? That's millions of years longer than all of history after the Cretaceous, which has spanned 65 ^note  Or perhaps closer to 66, if recent studies are to be believed million years. Wouldn't it be better to go visit it any other day but the one guaranteed to kill you? And must it always be right at the impact zone at that?

This is when The Theme Park Version of prehistory reveals its dark side for time travelers. No matter how sophisticated the method of time travel used, the arrivers will always have to complete their tasks before the asteroid arrives. There is no way around it, sometimes even if you're observing Jurassic or Triassic dinosaurs. And if the Time Travel in question was random, it's even more astounding that EVERY protagonist gets sent back to the exact same date — not to mention within the blast radius, instead of any other location on the planet. ^note If arriving at any random point during the existence of non-avian dinosaurs, there is a 1 out of 64.6 billion chance to land on a specific date. Considering the margin of error in the date of the impact, even if you went to exactly (or roughly) 65 million years ago on purpose, the odds that the impact is going to happen while you're there must be minuscule even if you stayed there for the rest of your life.

This need not apply only to the K-Pg extinction. Fiction loves to flanderize history into simple compact events and travelers headed to other periods may find themselves in the midst of other disasters, like arriving in Manassas only to find a civil war is breaking out, or visiting Pompeii only for a volcano to erupt. Such a visitor is not looking to change history or see said famous event, they just want to take a stroll and breathe in the surroundings only to realize: "Oh, Crap! This 20th century ship I'm on is called the Titanic!"

Sometimes this is explained by showing that the protagonists caused the event in question. It turns out that They Already Changed The Past, and the only reason history books record that particular event happening on that particular day is because the time traveller just happened to appear at that time and place, by chance.

Related to In the Past, Everyone Will Be Famous. As noted above, it may be part of a Phlebotinum Killed the Dinosaurs plot, or The Dinosaurs Had It Coming.

Compare It's Always Mardi Gras in New Orleans, where regular travel always happens to coincide with famous events.

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Examples involving the K-Pg extinction:

Anime and Manga

• In GaoGaiGar, ChoRyuJin's trip to the past coincided with the K-Pg event because they inadvertently caused it when they pushed the asteroid back through a wormhole to keep it from falling in the present.

Fanfiction

• Prehistoric Earth: In the t. rex rescue mission, A Continent of Blight, the rescue team for the titular park travel to the late Cretaceous period just in time to rescue the T. rex and various other late Cretaceous Hell Creek fauna from the infamous meteor impact...with team leader Drew ending up temporarily marooned in the past after said meteor impact.
• Prehistoric Park Reimagined: In the story's t. rex mission Return of the King, the titular park's rescue team travel back in time to a little over 36 hours before the infamous asteroid strikes for the sake of rescuing t. rex and as many other local Cretaceous period Hell Creek fauna as possible for the park.
• In Swing123's Triassic Park: Into the Past, Calvin and Hobbes end up in the late Cretaceous Period, three days before the K-Pg Extinction Event.

Films — Animated

• Subverted in Disney's Dinosaur. Since it's a dinosaur movie, we get the obligatory asteroid strike to kick off the plot, but it's not the asteroid strike — its damage appears to be confined to a relatively small area, and the dinosaurs in the cast manage to survive by migrating en masse to the nearest fertile area.

Films — Live-Action

• 65: No time travel is involved but it's otherwise played incredibly straight. Two Human Alien survivors of a spaceship crash find themselves on prehistoric Earth during the time of dinosaurs. But not just any time, they have the incredible misfortune to land on the planet less than one day before the cataclysmic Colony Drop. It's partly justified; they only got stranded on the planet when smaller asteroids, debris surrounding the big one, impacted their ship in outer space. What's a little less justified is that they happened to crash at the exact spot the meteor is also going to crash.

Literature

• Inverted and lampshaded in the Italian children's book Aiuto, c'è un triceratopo in cantina!^note Help, there's a Triceratops in the basement!. The time-travelling protagonists want to witness the end of the dinosaurs, but it takes them a lot of trial and error to zero in on the right instant. When another character asks them why they don't quit mucking around and skip directly to the extinction bit, everybody else roll their eyes.
• Animorphs: In Megamorphs 2, a hole in space-time causes the Animorphs to accidentally arrive one day before the asteroid hit. They get into a tussle with several warring Ancient Astronauts trying to colonize Earth, the losing species attempting revenge by diverting the path of a passing comet. The meteor's strike creates another hole that lets the kids return to the present. It was one of the weirder books.
• In The Science of Discworld, the wizards and especially Rincewind see every asteroid and comet impact in Earth's ("Roundworld's") prehistory largely because they're fast-forwarding much of the time. It's still suspicious that they end up being virtually present at the moments of actual impact events — including the dinosaur-ending one.
• Scientists in Robert J Sawyer's End Of An Era travel back in time to the Cretaceous in order to study dinosaurs. Because of some uncertainty in the equations, they happen to arrive a couple days before the K-Pg Event. And for good reason, too. They caused it.
• The Magic School Bus book In the Time of the Dinosaurs has them escape from the asteroid at the end of their day in the Cretaceous, though also after visiting other periods; given that the purpose of the trip was educational, it's possible Ms. Frizzle secretly took them to the impact deliberately—and given that the bus can travel through time, the class isn't in any danger from it. It's averted in the corresponding animated episode however, where there is no asteroid because Ms. Frizzle sends them back 67 million years in the past.
• Justified in The Magic Tree House, where the eponymous treehouse is attuned to Time Travel to a collection of important historical events... which tend to include certain disasters. Most notably, Jack and Annie end up in Pompeii as Mt. Vesuvius erupts, on the RMS Titanic, and in San Francisco in time for the 1906 earthquake. (Ironically, the one time they do go to the Cretaceous period, there's no asteroid in sight.)
• Averted in The New Dinosaurs: An Alternative Evolution by Dougal Dixon, which speculates on how dinosaurs and pterosaurs may have evolved if the K-Pg extinction hadn't happened.
• Also averted in Lest Darkness Fall by L. Sprague de Camp. Martin Padway manages to stop the disastrous Gothic War in 535 AD and begins to repair the damage that the fall of the Roman Empire has done on Europe.
• Justified in Pathfinder (2010). The protagonist Rigg can travel back in time by identifying the "path" of a living thing that had walked the land before. In a moment of urgency he picks the most recent path of an extinct animal he sees, which turns out to be fleeing the Colony Drop that rendered it extinct.
• Justified in the Star Trek: The Original Series novel First Frontier, where the Guardian of Forever sends the Enterprise crew back to the asteroid strike because someone else has already prevented it.
• Timeriders likes to play with this trope. The second book involves ending up in the late Cretaceous with a dozen or so civilians, but despite the approximate date (about 62.5 million years BC - geology is wonderfully vague like that) the asteroid is not their primary mortality concern, but (in order) food and water, disease, predators and inbreeding. And the pack of highly intelligent and adaptable predators that have been stalking them for the last month.

Live-Action TV

In General:

• While they don't often involve time travel (with maybe one exception), many dinosaur documentaries which follow the life of an individual dinosaur are fond of ending their stories by having the asteroid impact. (If said documentaries are made by The BBC it's a pretty safe bet that they'll use Stock Footage from Walking with Dinosaurs to save money.)
  • Averted by Dinosaur Planet. All four stories are set in the Late Cretaceous, but during the Campanian epoch, several million years before from the K-Pg event, and there is nary an asteroid in sight. The only story showing the death of the main characters (Little Das' Hunt) is but a localized disaster.
  • Averted in Prehistoric Planet; while the series takes place at the end of the Cretaceous Period, the focus is placed on the evolutionary success of dinosaurs and the series ends on a hopeful note with a Hatzegopteryx flying off into the sunset.

By Series:

• In an episode of Between the Lions, Walter and Clay Pigeon get transported inside a book about dinosaurs. At first they believe they've scared off a T-rex with their roars, but then Lionel turns the page and they realize the T-rex was actually running from the meteor.
• With all the dinosaurs either being of Ambiguous Species or Jurassic and Cretaceous dinosaurs, living in a generic stereotypical prehistory, Dinosaurs could theoretically take place at any time during the Mesozoic, right? Nope. The last episode shows the start of the K-Pg extinction. (That was a deliberate choice of Torch the Franchise and Run on the showrunners' part, but still.)
• Doctor Who: While no dinosaurs (aside from a few fossilised bones) actually appear in "Earthshock", the final episode has Adric trying to prevent a space freighter from crashing into the prehistoric Earth, unaware that the freighter is destined to become the "asteroid" which caused the K-Pg extinction. Not only does he fail to stop the impact, he ends up dying in the resulting explosion. (Depending on your view of how time travel works in the Whoniverse, this is arguably justified: it's not that the freighter "happened" to arrive on Extinction Day; Extinction Day was going to be whatever day the freighter arrived on.)
• Non-time travel example: In the Distant Prologue ("distant" meaning "prehistory") to Power Rangers Dino Charge, Sledge chases the Keeper to Earth and shoots him down. The Keeper is able to retaliate by sneaking a bomb aboard Sledge's ship, which then drops the load of asteroids it was carrying.
• In the first episode of Prehistoric Park, Nigel must collect a T. rex for the park before the asteroid hits. He justifies this by saying that he wants to get a specimen that would have died shortly afterwards so the timestream won't alter too much. However, he later revisits the period on other trips involving significantly fewer asteroids.
  • Nigel Marvin's missions go back to periods of time where species are at the end of their line. He went back to before the meteor impact to get a T. Rex, and grabbed a Triceratops and a flock of Ornithomimus while he was there while trying to get a Rex to follow. His later missions to the period were after species that died out before this point, like Microraptor and Deinosuchus. The former did have a volcanic eruption go off, so at least two of his trips did involve giant explosions and dust clouds of death. The latter just had gigantic dinosaur-eating crocs from Texas.
• Inverted in Primeval. Abby and Connor are trapped in the Cretaceous for a year and have to fight to survive there. None of them are worried about the comet hitting Earth. They are much more worried about the Spinosaurus, which has his territory right next to them.
  • Played straight in the spin-off novel Extinction Event. A gigantic time anomaly is opening up in Siberia, and countless dinosaurs and other animals from the Late Cretaceous are coming into the present. Nick Cutter goes through this anomaly into the Cretaceous, and sees the comet in the sky. He realizes that they really are at the end of the Cretaceous period, and the comet will hit Earth in a few hours or weeks.
• Averted in Terra Nova. The temporal conduit does take people to the Cretaceous, but roughly 20 million years before the K-Pg extinction. (For context, 20 million years is longer than hominids of any kind have existed, much less human civilization.)
• This is pretty much the premise of The Time Tunnel. In theory, the Tunnel unpredictably sends the heroes to random eras; in practice, they always arrive while some famous, exciting event is happening, or about to happen.

Tabletop Games

• Justified in Predation, where the choice of just before the asteroid impact was intentional so as to minimize the risk of a butterfly effect (the mass extinction "washing out" any changes the humans might make). It would have been a good plan had time travel not abruptly stopped working.

Video Games

• Chrono Trigger has you traveling to 65 million BC, and in the conclusion of that part of the plot, a giant asteroid falls to the planet. Justified in that the asteroid that wiped out the remainder of the Reptites is actually Lavos, which is implied to be the source of the Gates that make time travel possible.
• Dino Run involves you out-running the Advancing Wall of Doom that is debris flying as a result from the asteroid impact.
• E.V.O.: Search for Eden ends the dinosaur era with a massive meteor bombardment, and makes a point of showing the Styracosaurus mother, who's child you saved in an earlier level, laying dead together huddled in fear.
• Nanosaur: By the year 4122, humanity is extinct and genetically engineered, intelligent dinosaurs rule the Earth. Problem is, due to their small genetic pool, inbreeding becomes a serious problem and they decide to send a velociraptor back to the Cretaceous era to collect various dinosaur eggs. You'll never play this game for more than 20 minutes, because that's all the time you have to complete your mission before the asteroid hits.
• The computer game Save the Dinosaurs, part of Dinosaur Adventure 3D, had you save a bunch of dinosaurs from all three time periods. You had until the comet struck the earth (the time to impact being depicted by a timer) to save all of them; even if you were in the wrong period to be affected, the time tunnels, or the hub area, it was game over if time ran out.
• The Journeyman Project Pegasus Prime invokes this with its historical log which contains unaltered historical information in case a rogue time traveler changes history. The Temporal Security Agency creates an artificial island back in the year 200 million BC, which is set in the late Triassic period, and hid it away inside a cliffside, safely protecting it from any wild predators. However, in a very short amount of time, the volcanic activity the Triassic/Jurassic extinction event was known for would occur, destroying the island completely preventing any of it from altering history.

Webcomics

• In Dawn of Time, Dawn and Blue are returned back to their own time just as the asteroid is about to hit. They don't escape the asteroid, but they do manage to get away from the Grim Reaper.

Web Video

• Puppet History: In Season Five, The Professor is trapped in the Cretaceous Period, but is taken in by two kind dinosaurs who decide to raise him as their son. They spend a few happy months together, with The Professor wanting to return to his own home and time, but also loving his new family and enjoying seeing the period in person. At his dino parents' request, he does eventually explain how the dinosaurs will eventually go extinct, but assures them that they don't need to worry about it. After all, what are the odds that he landed right at the tail-end of the period's 79 million year period? No points for guessing what happens in the Season Five finale. The Contrived Coincidence is deliberate, with the point being that in life, you don't really know what hand you've been dealt or what's coming up next—so make the most of it, and let the people you love know how you feel. The Professor and his parents just barely escape the asteroid's impact, thanks to a well-placed genie wish from Ryan in the future.

Western Animation

• Back to the Future also pulled this out, with Doc Brown and Verne stopping a meteor from hitting to save a dinosaur they befriended, only to find out it was that one, and without it, dinosaurs still rule the earth.
• Justice League Unlimited:
  • Invoked in "The Once and Future Thing." Lord Chronos punishes his goon Chucko by stranding him in the Cretaceous at the moment of the meteor's landing. At the site of the meteor's landing. Leads to some hilarious last words.
    Tyrannosaurus rex: *roars*
    Chucko: You think I'm scared? *ignites dual-bladed lightsaber* I'll be running this dump in a few yea... *turns and sees asteroid* Oh, phooey...
  • Chronos, back in the present, then asks the rest of his goons, "Do you know what killed the dinosaurs? Well, Chucko does."
• Happens during an Imagine Spot episode in one of Albert Barillé's Il était une fois... cartoon series. The kids are time travelling (with their imagination!) and they stop for a walk 65 million years BC. The storyteller is a bit dumbfounded at first trying to remember why that date is stuck in his mind before he realizes it, gets the children on the time machine and they depart seconds before the asteroid hits. Your Mind Makes It Real... perhaps a bit too much.
• An episode of Robot Chicken had various dinosaurs banding together to build a spaceship to head off the asteroid and failing miserably. It turns out this is a story told by George W. Bush explaining why they are extinct.
• The 2003 Teenage Mutant Ninja Turtles zigags this trope. At a point in the Cretaceous Period, the turtles travel back to prevent a plan by a villain that would cause the asteroid in the K-Pg extinction to narrowly miss the Earth, temporarily lose MacGuffin that would allow them to return to the present for a few days before finding it at the end of the episode. During the episode, we see a bright red dot in the sky that Donatello assumes is the asteroid in the distance, but he admits that he doesn't know when its going to hit and when he doesn't know if they'll get back to the present, he guesses it could be anywhere from weeks to years.

Other

• The Disney ride based on Dinosaur mildly averts this by claiming initially you would have gone on a tour of the peaceful early Cretaceous, but a rogue researcher changed your arrival date to just before the extinction event because he wants to rescue Aladar, the film's hero.

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Examples involving other historical events:

Films — Live-Action

• Time Bandits has Kevin and the dwarves arrive on the Titanic not long before it sinks.

Literature

• In Doomsday Book, time traveler Kivrin arrives at the start of the Black Death epidemic of 1348, twenty years later than she intended to arrive. The explanation is that history resists people from going to any time but specific dates, hence why she must arrive in 1348.
• This happens many times during The Magic Treehouse series. It's justified because the books are usually meant to take them to a specific event like the Pompeii eruption, but Jack and Annie often don't bother to read further in the book until said disastrous event is happening. Ironically, this is averted in the first book when the duo end up in the late Cretaceous, and there's not an asteroid in sight.
• In Timeline, a medieval history teacher and his students, working in an archaeological dig at a (fictional) ruined castle in France, travel to 1347 - mere days before the castle was taken by the English during The Hundred Years War. The trope is played even more straight when they return to the present and kick the Jerkass Corrupt Corporate Executive that built the time machine into the time machine, sending him to the same place... in 1348, just as the Black Plague arrives. Since he never comes back, they assume he caught it and died. The Film of the Book condenses this and just has the guy thrown into the Final Battle in 1347, right in time to get a sword strike to the head.
• Timeriders is interesting, as mentioned above. Because of alternate timelines, examples include accidentally landing on the lawn of the White House minutes before a Nazi invasion, prolonging the siege of Nottingham for about a week (in-universe predictions held it to hours at best under the pressure of Richard I's armies) and the fact that one of the team was a steward on the Titanic is explained thoroughly; the Agency needed to know exactly when and where these teenagers would have died. What better than someone known to have been missing in action at the bottom of the ship in one of the most infamous voyages of the twentieth century?

Live-Action TV

• This is often the driving plot device of Doctor Who. The Doctor and his companions will arrive at some key moment in time just before a volcano explodes, a ship sinks or a war breaks out (and usually find an alien plot behind it). Eventually, the personification of the TARDIS explains why, and it's exactly what fans had speculated for decades:
  The Doctor: You didn't always take me where I wanted to go.
  Idris: No, but I always took you where you needed to go.
  • Even his trips into the future fit the trope. If he visits anything ever it's practically guaranteed to precipitate large-scale deaths in some incredible fashion.
• Invoked in Loki (2021) by the rogue Variant, who is able to avoid attracting TVA attention by hiding at apocalyptic moments in time — you can't alter the timestream enough to make a noticeable difference if everyone you're affecting is dying in an hour anyway. After Loki deduces this, he and Mobius test this by visiting Pompeii and making a scene in the town just as Mount Vesuvius erupts. It's later shown the TVA itself invokes this by sending everything from the errant timelines they "prune" to an apocalyptic event at the "end of Time", where they are devoured by Alioth.
• Prehistoric Park may play the trope straight in the first episode, but Nigel's other trips follow other periods due to a desire to get animals at their end of their ropes, which minimizes paradoxes. At two different points he travels to points in time where his target species are in fact quite common: first the Mammoth in his second trip in episode 2, and later the Smilodon in episode 4. He didn't try and get any of them then and when he did get their respective species it was in the first and second trips of their episodes respectively. He did grab a woolly rhino and a terror bird during those trips, as those species were at the end of their time, though only the terror bird was planned.
• Intentionally subverted in Quantum Leap, where Sam's time-traveling missions (as determined by an unknown entity) only involved fixing the lives of normal people, never celebrities. The closest that he came to do so was when he tried to prevent John F. Kennedy's assassination, and succeeded only in saving his wife (who, in the original timeline, had also been killed).
• Red Dwarf: When Lister insists on using a time machine to go back to 21st century Earth and order a few thousand curries, the time machine misses, and winds up depositing them in Dallas, on the day of JFK's assassination. Right in the book depository as Lee Harvey Oswald's lining up his shot.
• The Time Tunnel. If the protagonists ended up in a place where a historic event took place, they always arrived just before said event occurred. Indeed, the very first episode sends them to the Titanic.
• In The Twilight Zone (1959) episode "There's No Time Like the Past" this was being done intentionally at first, as a man goes back in time to attempt to warn the people of Hiroshima about a nuclear bomb in 1945 (hours before it hit), prevent the sinking of the RMS Lusitania (hours before it was torpedoed), and kill Adolf Hitler before World War II. But when he decides to stop trying to change the past and go live in 1881, this trope still comes into play. He arrives the day before President James Garfield is assassinated, but decides to let it happen. Then it turns out he arrived a few days before a huge fire killed some children at the local schoolhouse, and he struggles with whether or not to prevent it, only to end up causing it when he does try to intervene.
• Every episode of Voyagers! entailed this, since the whole point was to Set Right What Once Went Wrong.

Western Animation

• In the Family Guy episode "Road to Germany", Brian and Stewie travel back in time to Warsaw, Poland (though how they got to Poland from Rhode Island is never explained), September 1st, 1939. The date that Germany invades Poland and kicks off World War II (the Germans did not reach Warsaw until a week later). They have time for one Jewish wedding before tanks start rolling in.

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