The year is 2055. A hunter known simply as "Eckels" prepares to take the trip of a lifetime: going back in time to the Mesozoic to hunt the greatest predators that ever lived. However, when he goes back to the Late Cretaceous he panics when confronted with a Tyrannosaurus rex, and falls off the path and crushes a butterfly, breaking some of the myriad of rules the time agency has to keep the time line from changing. When the party returns to the future, they find out that the world has changed for the worse. In the original timeline, the United States presidential election was recently won by Keith, a fairly moderate candidate, as opposed to Deutscher, a fascist extremist. However, in this changed timeline, the reverse is true (words and phrases are also spelled differently). A distraught Eckels pleads with Travis, the guide, to take him back in time and fix what he's done, but Travis, having previously warned him that it's impossible (the time machine skips over any moment in history that they've already visited, due to Never the Selves Shall Meet), silently lifts and fires his rifle, presumably at Eckels.
First written by Ray Bradbury as a short story for Collier's magazine in 1952, "A Sound of Thunder" has become the most republished science-fiction story of all time. Its influence can be seen all over the fictional world, particularly due to its introduction of the Time Travel plot in which "small changes in the past snowball into the future". It is one of the Trope Namers for Butterfly of Doom, which is... well, exactly what it stated above. This story has also led to the creation of numerous other works, including a spin-off novel series and the short story series Rivers of Time. Oh, and a movie, released by Warner Bros. in 2005.
Not to be confused with the Pink Floyd live album/concert film A Delicate Sound Of Thunder.
The short story contains examples of:
- All Germans Are Nazis: The fascistic candidate Deutscher's name is based on the German word for German.
- Close-Enough Timeline: Travis actually theorizes about this before the hunt began.
- Dumb Dinos: The T. rex is described as monstrous and devoid of emotion, but also awesomely majestic.
- For Want of a Nail: The seemingly inconsequential death of a prehistoric butterfly manages to result in a political victory of A Nazi by Any Other Name in the modern day and possibly mainstream society's embrace of Fascism, while changing the basics of English grammar and graphemes.
- Godwin's Law of Time Travel: The Ur-Example, although Deutscher is only Nazi-like rather than full-on Nazi.
- In Spite of a Nail: Despite changing the political landscape just enough to ensure the rise of Fascism and the basic tenets of the English language, nothing else of major importance seems to have changed in the modern day. Then again, we only see a few of the changes to the modern timeline before the end of the story. . . given the obvious changes already shown, who the hell knows what else is different?
- Ripple Effect-Proof Memory: The travelers and their tour guides are the only ones who seem aware of the changed Bad Future.
- Stay on the Path: Or else!
- Stock Dinosaurs: The only dinosaur that appears in the entire story is the infamous Tyrannosaurus rex.
- A Storm Is Coming: The phrase "a sound of thunder" occurs a couple of times in the story, each time prefiguring danger.
- Temporal Paradox: Subverted when the safari guides explain that "Time steps aside" to prevent such paradoxes from happening.
- Time Travel for Fun and Profit: Travis' agency organizes safaris into the past for big game hunters.
- Title Drop: Twice in the narration.
- What Could Possibly Go Wrong?: Who thought it was a good idea to make big-game time travelling, knowing full well what the risks and consequences were? What sort of monetary gain could be worth the risk of waking up one morning to have never existed? Simple: Screw the Rules, I Have Money!.
The spin-off novel series contains examples of:
- Abusive Alien Parents: The Mutata send their young off to be raised by other Mutata.
- Always Chaotic Evil: The sentient Allosaurs.
- Rule of Cool: Alternate universes filled with dinosaurs, samurai, sapient pterodactyls, cyborgs, and Aztecs. At one point it is hinted that there is even an entire universe filled with cat people.