Ben Crandall (Ethan Hawke) keeps having a dream about traveling over a circuit board. He then draws it and shows it to his brainy friend [[{{Geek}} Wolfgang]], who builds the board which is able to create a force field bubble. The two boys, along with help from their new tough friend Darren, decide to build a spaceship out of old amusement park ride parts that when used with their new found technology gives them the ability to travel into space.

They create a spaceship and call it the "Thunder Road", and they fly into space. Not long afterwards, they explore an alien spacecraft that they get sucked into.

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!!The movie contains examples of the following tropes:
* FiveFiveFive: The zip code on Ben's jacket is 21499. While the 214XX is indeed Maryland (matching his address), the "21499" zip code itself is not in use in the United States.
* AliensSpeakingEnglish: Justified, they mostly speak in pop-culture references.
* AliensStealCable: And quote it relentlessly.
* AlwaysABiggerFish: [[spoiler: The Thunder Road is swallowed by a large spaceship. Then that one is swallowed by a larger one in the same way.]]
* AscendedFanboy: All three boys count.
* BizarreAlienBiology: And how.
* BoldExplorer: All three protagonists fit the bill, as they boldly set off to hunt for aliens in their new ship.
* TheCastShowoff: Robert Picardo. He just cuts loose with his impersonations and comic beats.
* CaliforniaDoubling: Ben's jacked clearly states that his address is in Maryland, but the movie was filmed in California. The vegetation is a giveaway.
* CoolSpaceShip: The Thunderroad, sorta. Wak and Neek's, too. [[spoiler:And their Dad's ship.]]
* ConspicuousCG: The dream sequences.
* CrazyCulturalComparison: The aliens can only talk human using television quotes.
* TheEighties: The setting.
* FreeRangeChildren: All three kids work well into the night at the creek. If their parents were looking for them, we never find out.
** They also manage to stay out all night and come home the night of the first flight ''with their clothes and breath smelling like beer'' from christening the Thunder Road.
* GravityIsAHarshMistress: The "Gravitational Cognizance" sort - the characters don't fall until they ''realize'' they should be falling. This happens when they return to earth the final time.
* HumansAreBastards: The reason the space teens didn't want to visit Earth.
* IComeInPeace: One of the kids greets an alien with this, because it seems like the right thing to say. The alien, in turn, replies, "[[Characters/BugsBunny Ehhh, what's up, doc?]]"
* InterspeciesRomance: Neek and Wolfgang seem to have some cross-species PuppyLove going.
* JerkAss: The [[spoiler: father alien]].
* JustPlaneWrong: The helicopter's amazing night of flying. The Thunder Road is flying when the Drive In is open - evening, between 9pm and 1am. The helicopter encounters it shortly after the Drive in. We next see the helicopter landing in broad daylight, late enough in the morning the newspapers have been published and are available. That's easy 7 hours of flight that evening - a long time for that kind of helicopter to be just tooling around.
* LargeHam: The father alien.
* TheMothership
* MythologyGag: There's one to Kingston Falls, the setting of Creator/JoeDante's previous film ''{{Gremlins}}''.
* NoEndorHolocaust: The Thunder Road crashes through a crowded concession stand. No injuries.
* NoPlansNoPrototypeNoBackup: [[spoiler: The ship sinks and it becomes obvious Wolfgang hasn't saved any of the programming work at all on disk - everything was in the ship.]]
* PowerPerversionPotential: The first thing Ben uses the force field they made to is spy on a girl he loves.
* TheReasonYouSuckSpeech: Ben's reponse to [[spoiler: The father alien's refusal to let the kids stay. And for being an all around jerk]].
* RealityIsUnrealistic: An in-universe example. The Thunder Road, actually flying around, passes in front of a drive-in screen showing a cheesy sci-fi movie, prompting a moviegoer to snark "That looks so fake!"
* ReCut: Joe Dante hated the theatrical cut and was allowed to re-edit the movie for home video release by deleting a few sequences (one of which explains why River Phoenix's character skipped school to work in his lab) while restoring a few small snippets (the video version is three minutes shorter than the theatrical cut as a result). Some of the deleted sequences appear as extras on the DVD.
* ShoutOut: The film was directed by Joe Dante, so it's expected. Examples that haven't already been mentioned include:
** The toy monkey from ''Film/CloseEncountersOfTheThirdKind'' can be seen in Wolfgang's basement.
** The rat, Heinlein, is named after ScienceFiction author Creator/RobertAHeinlein.
** Sound effects from ''YarsRevenge'' can be heard in the [[ShowWithinAShow drive-in movie]].
** [[CitizenKane Rosebud]] can be seen at the top of a junk pile when the boys build the Thunderroad.
** Charles M. Jones Junior High School is named after, [[CaptainObvious unsurprisingly]], Creator/ChuckJones.
*** There's other LooneyTunes references throughout the movie. Including the hole the sphere at the beginning makes being shaped like Bugs Bunny's head.
* ShowWithinAShow: See the "Stylistic Suck" entry.
** A few other movies like ''Film/TheCrawlingEye'', ''Film/TheDayTheEarthStoodStill1951'', ''Film/EarthVsTheFlyingSaucers'', ''Film/ThisIslandEarth'', and 1953 version of ''Film/{{The War Of The Worlds|1953}}'' are also featured.
* SpeaksInShoutOuts: The aliens, courtesy of EnglishFromWatchingTelevision.
* StylisticSuck: The [[ShowWithinAShow Movie]] at the drive-in is pretty much this.
* TheGenieKnowsJackNicholson: As a side effect of learning all earth languages and culture [[AliensStealCable from television]], Wak's dialog consists mainly of celebrity impersonations and pop culture jokes. Neek is a little more subtle, but also does clear impersonations of MarilynMonroe and Creator/IngridBergman.
* TheUnintelligible: The father alien. You can barely make out a few lines though.
* WhateverHappenedToTheMouse: The helicopter pilot's plot is dropped after the space trip, and has little bearing on the larger plot.
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