When a script has a character as unique as Ferris Bueller or Marty McFly or the Dude, finding the right actor to play the role is absolutely crucial. A brilliantly written character will fall flat on-screen if they’re miscast, and this is particularly true of a comedy character.

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Luckily, more often than not, Hollywood hits the mark. Matthew Broderick was the perfect person to play Ferris, Michael J. Fox was the perfect person to play Marty, etc. But before landing on those perfect choices, the producers have usually considered a bunch of other actors.

Jonah Hill As Alan Garner In The Hangover

Zach Galifianakis in The Hangover and Jonah Hill in The Wolf of Wall Street

According to Indiewire, the role of Alan Garner in The Hangover was originally written less as a bizarre man-child and more as a burdensome younger brother that the guys were forced to bring with them. When the character was written like this, Jonah Hill was the top choice.

When the role was rewritten into his more familiar form, it became clear that it didn’t need an established star. It needed an undiscovered comedic genius like Zach Galifianakis to make the role his own and run with it.

Ben Stiller As Brian Fantana In Anchorman: The Legend Of Ron Burgundy

Paul Rudd in Anchorman and Ben Stiller in Zoolander

According to Vulture, Adam McKay and Will Ferrell’s first draft of their absurdist gem Anchorman: The Legend of Ron Burgundy included casting suggestions for all the main roles. Obviously, Ferrell was always going to play Ron, but the rest of the news team was different: John C. Reilly as Champ Kind, Chris Parnell as Brick Tamland, and Ben Stiller as Brian Fantana.

In the final movie, these roles were played by David Koechner, Steve Carell, and Paul Rudd, respectively. Stiller instead has a cameo appearance during the news team battle, Parnell plays the smaller role of Garth, and Reilly went on to co-star with Ferrell in Talladega Nights, Step Brothers, and the considerably less enjoyable Holmes & Watson.

David Letterman As Ted Striker In Airplane!

Robert Hays in Airplane and David Letterman on Late Show

The casting of the classic spoof Airplane! was unique, because the filmmakers weren’t looking for comedians or actors with a background in comedic delivery. Instead, they wanted to cast regular actors who would deliver the ridiculous dialogue straight. This ended up turning a previously straightforward dramatic actor, Leslie Nielsen, into one of the most revered comedy stars in the world.

According to the directors’ DVD commentary, the lead role of Ted Striker (ultimately played by Robert Hays) was written for David Letterman. However, after doing a screen test in 1979, ZAZ decided to pass on the soon-to-be Late Show host.

Mindy Kaling As Lillian In Bridesmaids

Maya Rudolph in Bridesmaids and Mindy Kaling in The Office

Paul Feig ended up assembling the perfect ensemble around Kristen Wiig for Bridesmaids, but not everybody in the movie was the first choice for their role. For instance, Wiig’s SNL cohort Maya Rudolph was ultimately the right choice to play her bride-to-be best friend, Lillian, even if she wasn't the initial pick.

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According to USA Today, Mindy Kaling originally auditioned for the part. Kaling explained on Watch What Happens Live, “They called me in for Maya Rudolph’s part, and I practiced it so much and I was so into it, and I love that whole cast. That one was a heartbreaker.”

Seth Rogen As Seth In Superbad

Jonah Hill in Superbad and Seth Rogen in The Interview

Seth Rogen and Evan Goldberg began writing their high school comedy Superbad when they were actually in high school, and the fact that the lead characters are called Seth and Evan is a dead giveaway that the script is at least semi-autobiographical.

According to Vulture, Rogen originally intended to play Seth himself, but since the movie didn’t get made until he was in his 20s, he was too old to convincingly play a high schooler. Despite being less than two years younger than Rogen, Jonah Hill could convincingly play a high schooler, and the lead role in Superbad catapulted him to stardom. Rogen instead played Officer Michaels, one of the cops who hang around with McLovin all night.

Anthony Michael Hall As Ferris Bueller In Ferris Bueller’s Day Off

Matthew Broderick in Ferris Bueller's Day Off and Anthony Michael Hall in The Breakfast Club

While it’s impossible to imagine anybody but Matthew Broderick playing the title role in John Hughes’ iconic carpe-diem comedy Ferris Bueller’s Day Off, he wasn’t the only casting choice.

Alan Ruck, who ultimately played Ferris’ best friend Cameron, told The A.V. Club, “They had originally offered the Ferris part to Anthony Michael Hall... and I think Mike – that’s what everybody calls Anthony Michael Hall – had done four movies with John, so I think he wanted to do something different.”

John Wayne As Major Kong In Dr. Strangelove

Slim Pickens in Dr Strangelove and John Wayne in The Searchers

According to A Grand Guy: The Life and Art of Terry Southern, Lee Hill’s biography of Dr. Strangelove co-screenwriter Terry Southern, the role of stern-faced military tyrant Major Kong was originally written with western star John Wayne in mind.

Peter Sellers initially wanted to play it as his fourth role in Kubrick’s masterful political satire, but an injury prevented him from playing more than three characters. The role was offered to Wayne, but he instantly turned it down and the part went to Slim Pickens.

Richard Pryor As Sheriff Bart In Blazing Saddles

Cleavon Little in Blazing Saddles and Richard Pryor performing standup

To put together the relentlessly ludicrous screenplay for his groundbreaking western spoof Blazing Saddles, Mel Brooks assembled a team of writers that included Norman Steinberg, Andrew Bergman, Al Uger, and possibly the greatest standup comic who ever lived, Richard Pryor.

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According to Salon, Brooks wanted to cast Pryor to star as Sheriff Bart, but the studio refused to fund the movie with Pryor in the lead role, because his history of drug arrests had made him uninsurable. So, Cleavon Little was cast, and he knocked the role out of the park.

Eric Stoltz As Marty McFly In Back To The Future

Michael J Fox in Back to the Future and Eric Stoltz in Pulp Fiction

Eric Stoltz wasn’t just considered for the role of Marty McFly in Robert Zemeckis’ classic time-traveling comedy Back to the Future; he was actually cast and shot five weeks’ worth of scenes opposite Christopher Lloyd’s Doc Brown. Michael J. Fox was always the top choice, but it didn’t seem like he could get out of his TV commitments to shoot the movie.

However, after those five weeks, it was clear that Stoltz wasn’t working out. He’s a great actor, but according to Den of Geek, Stoltz’s take on the Marty McFly character was too intense. Fox was able to work around his TV schedule and the rest is history (well, history is gonna change).

Mel Gibson As The Dude In The Big Lebowski

Jeff Bridges in The Big Lebowski and Mel Gibson in Braveheart

While Jeff Bridges wound up being so perfect for the role of Jeff “The Dude” Lebowski that he inspired a religious following, the Coen brothers originally considered a much different actor to lead their classic stoner noir The Big Lebowski.

Since the duo had no particular actor in mind for the part, they decided to go straight for the biggest actor in Hollywood, who at the time was Mel Gibson. However, according to Rolling Stone, Gibson didn’t take the Coens’ Lebowski pitch very seriously.

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