When it comes to movies about time travel, one stands head and shoulders above the rest. But Robert Zemeckis’ Back to the Future is much more than just a film about traveling through time; it’s praised as one of the greatest comedies, one of the greatest science fiction movies, and one of the greatest movies ever made, period.

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Nearly four decades later, Back to the Future still holds up as a timeless classic. But what elements of the movie make it so endlessly rewatchable?

Michael J. Fox’s Hilarious Turn As Marty McFly

Michael J Fox in the middle of Hill Valley in Back to the Future

Ultimately, what anchors Back to the Future and makes the movie work so well is Michael J. Fox’s performance as Marty McFly. If he didn’t sell the existential terror of being trapped in the past, the audience wouldn’t have bought the reality of the plot.

On top of being extremely likable and having pitch-perfect comic timing, Fox plays Marty as convincingly flustered when he finds himself stuck in the ‘50s.

Airtight Story Structure

Christopher Lloyd and Michael J. Fox by the DeLorean in Back to the Future

Robert Zemeckis and Bob Gale’s Back to the Future script is one of the greatest screenplays ever written. It has an airtight structure – every scene and every line of dialogue needs to be there to move the plot forward.

There’s a ton of exposition in the opening act, but it’s all important because it all comes back later. And not only does Back to the Future have a meticulously crafted plot; Zemeckis and Gale managed to find plenty of room for jokes as well.

Relatable Stakes

Marty and George perform the same action in Back to the Future

The problem with a lot of modern blockbusters is that the apocalyptic stakes of the conflict aren’t remotely realistic. The refreshing thing about Back to the Future is that the stakes are low enough to be relatable, but they’re still sky-high for Marty himself.

The world isn’t going to end if Marty doesn’t get back to the future, but if his parents don’t get together, he’ll never be born, and if he doesn’t channel a lightning bolt at the exact right second, he’ll be stranded 30 years before his own time.

Christopher Lloyd’s Dual Performance As Two Doc Browns

Christopher Lloyd as Doc Brown in Back to the Future

While Michael J. Fox plays one version of Marty throughout Back to the Future, Christopher Lloyd had the challenge of playing two versions of the same character – and he nailed both. And although many actors were in contention for the role of Doc Brown, Lloyd proved exactly why he was the perfect choice for the part.

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Both as Marty’s friend in 1985 and as an unsuspecting scientist that Marty has to convince he’s from the future in 1955, Lloyd evokes all the classic mad scientist performances while putting his own fresh spin on the archetype.

All The Foreshadowing

Doc Brown's clock in Back to the Future

Like Edgar Wright’s Cornetto movies, Back to the Future’s early scenes are filled with plants that are paid off later in the story. If anything, Back to the Future is a movie that works better on repeat viewings because its first act is filled with clever foreshadowing.

From the Harold Lloyd clock hinting at Doc’s climactic action to the line “history is gonna change” unwittingly setting up an adventure across the spacetime continuum, Back to the Future is jam-packed with foreshadowing.

The Escapist Tone

A picture of Michael J Fox as Marty McFly in Back to the Future is shown.

All the best movies of the ‘80s were marked by their sense of pure escapism: The Empire Strikes Back, Raiders of the Lost Ark, Die Hard, Batman, and indeed, Back to the Future.

While Back to the Future is primarily a comedic sci-fi story, Zemeckis frames it as a Frank Capra-esque fantasy movie in the vein of It’s a Wonderful Life, and the soulfulness of the story is what grounds all of the absurdity in a way that can actually move fans emotionally.

Countless Quotable Lines

Biff and Michael J. Fox as Marty McFly in Back to the Future

From “Great Scott!” to “Nobody calls me chicken!” to “Wait a minute, Doc, are you telling me you built a time machine... out of a DeLorean?,” Back to the Future is filled to the brim with quotable lines.

Even the exposition is quotable: “If my calculations are correct, when this baby hits 88 miles per hour, you’re gonna see some serious sh*t.”

Alan Silvestri’s Catchy Score

Marty playing the guitar in Back to the Future.

Alan Silvestri had a unique challenge coming up with the music for Back to the Future. He had to create a sound that captured both small-town whimsy and time-altering sci-fi spectacle.

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The big, sweeping score that Silvestri eventually composed managed just that. Every shocking plot twist in Zemeckis and Gale’s script is bolstered by the perfect musical accompaniment.

The Cliffhanger Ending

Doc, Marty, and Jennifer at the end of Back to the Future

After Back to the Future’s happy ending, just as Marty is about to go on a trip with his girlfriend Jennifer, a panicky Doc Brown shows up in futuristic garb and tells his young companion, “It’s your kids, Marty! Something’s gotta be done about your kids!”

Marty and Jennifer get in the DeLorean and Doc tells them, “Where we’re going, we don’t need roads,” before flying off into the distant future. This is one of the greatest sequel setups of all time.

Doc & Marty’s Endearing Dynamic

Michael J. Fox and Christopher Lloyd in Back to the Future

While the conflict of Back to the Future revolves around Marty trying to ensure the existence of his family, the central dynamic is his timeline-hopping friendship with Doc Brown.

There’s no explanation for why Doc and Marty are friends, but that doesn’t matter, because Fox and Lloyd share impeccable chemistry in those roles and their friendship is endearing.

NEXT: 10 Things About Raiders Of The Lost Ark That Still Hold Up Today