John Hughes’ high school classic Ferris Bueller’s Day Off is one of the most beloved comedies ever made. Everyone remembers the characters and everyone can quote all the most memorable lines from the movie (“Bueller?...Bueller?...Bueller?”), but did you know that a lot of those iconic lines were ad-libbed by the cast? Or that Hughes wrote the movie’s script in less than a week? Or that Cameron’s dad’s Ferrari wasn’t a real Ferrari? Life moves pretty fast – if you don’t stop and look around once in a while, you could miss it – so here are 10 Behind-The-Scenes Facts About Ferris Bueller’s Day Off.

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Edie McClurg improvised a lot of Grace’s lines

Grace the Secretary smiling at the viewer in Ferris Bueller's Day Off

Edie McClurg played the role of Grace, Ed Rooney’s secretary in Ferris Bueller’s Day Off, and if you think she’s one of the funniest characters in the movie – which, let’s face it, she is – then you probably have McClurg herself to thank. She ad-libbed a lot of her character’s lines, including the scene in which she pretends to be Rooney while on the phone to Cameron. She also improvised her line about how popular Ferris is: “He’s a righteous dude.” McClurg has always been known for playing sweet Midwestern characters, but she’s also a brilliant standup comedian.

Ferris’ parents got married (and later divorced) in real life

Although they’re not the focal point of the story – in fact, specifically avoiding them is an important plot device – Ferris and Jeanie’s parents are prominent characters in Ferris Bueller’s Day Off. The mom was played by Cindy Pickett and the dad was played by Lyman Ward. These two actors ended up getting married in real life. Unfortunately, their union didn’t last as long as their characters’ did, and they got divorced in 1992. These two aren’t even the only couple to come from the set of this movie – Matthew Broderick and Jennifer Grey, who played siblings in the movie, would later get engaged.

The fancy restaurant should be familiar to ‘80s movie fans

Any ‘80s movie buffs should be able to recognize the fancy restaurant that Ferris takes his friends to when they get to Chicago. It was featured in two other ‘80s classics besides this one. In the classic comedy The Blues Brothers, it’s the restaurant where Jake and Elwood Blues show up to act obnoxiously and terrorize diners until their trumpeter, now the maître d’, agrees to join the band. And in the classic drama St. Elmo’s Fire, perhaps the finest hour of the so-called “Brat Pack” that John Hughes helped to curate, it’s the restaurant where Kirby waits for Dale.

Charlie Sheen went 48 hours without sleep to play a drug addict

Charlie Sheen in Ferris Bueller's Day Off

Charlie Sheen has a cameo appearance in Ferris Bueller’s Day Off as a drug addict who hits on Jeanie at the police station. To convincingly play his drug-addled character, Sheen forced himself to stay awake for 48 hours before the shoot. Jennifer Grey had suggested Sheen for the part after they had appeared in Red Dawn together. Sheen’s character was originally much more crucial, with a backstory establishing him as an old friend of Ferris’. Ferris failed to save him from getting hooked on drugs and dropping out of school and feels responsible, which would’ve explained why he was so desperate to show Cameron a fun time.

John Hughes wrote the script in less than a week

Alan Ruck Mia Sara and Matthew Broderick in Ferris Buellers Day Off

Despite the fact that most writers would struggle to write a comedy that’s as hilarious and fresh and inspired and well-crafted as Ferris Bueller’s Day Off if they were given all the time in the world, it only took writer-director John Hughes less than a week to bang out the finished script.

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One report has it that he wrote it in six days, while others claim it was as short a period as two days. Hughes charted his progress with the script in a notebook. He was known for writing scripts for such classics as Pretty in Pink, Sixteen Candles, and Planes, Trains, and Automobiles in less than a week.

Matthew Broderick improvised the clarinet scene

The scene in which Ferris attempts to play the clarinet poorly and then tells the camera, “Never had one lesson!” was entirely improvised by Matthew Broderick. John Hughes made the interesting decision to break the fourth wall in Ferris Bueller’s Day Off. It’s unclear if Ferris knows he’s in a movie that’s been written and directed and shot by people, like Deadpool does, but he does know that there’s an audience watching him and he does frequently talk to them. It helped to endear moviegoers to the character immediately, because they felt like they knew him intimately. It’s surprising that it hasn’t been ripped off more.

Emilio Estevez turned down the role of Cameron

Apparently, John Hughes first offered the role of Cameron to Emilio Estevez, who was one of the biggest stars in the world in the ‘80s, but Estevez turned it down. This paved the way for Alan Ruck to take the role, a role that he credits with giving him his entire career. “Every time I see Emilio, I want to kiss him,” Ruck would later say. “Thank you!”. Ruck has the older look (owing to the fact that he was 29 at the time of shooting) and the awkward goofiness to really sell Cameron’s emotions in a way that Estevez, with his effortless charisma and leading-man looks, likely couldn’t have.

Ferris Buellers Day Off Ferrari

In Ferris Bueller’s Day Off, the title character talks his friend Cameron into taking his father’s Ferrari out for a joy ride. They end up crashing the Ferrari into the woods while ill-fatedly attempting to reverse the odometer. As it turns out, that wasn’t a real Ferrari. It would’ve been far too expensive for the producers to rent a real Ferrari for all the shoot days that would’ve required the car, so they had three replicas made up instead. Each replica was made using an MG chassis with a fiberglass body added over the top of it to make it resemble a Ferrari.

Some big names were considered for the role of Ferris

Robert Downey Jr wearing the white Avengers suit in Avengers: Endgame

Before John Hughes settled on Matthew Broderick for the role of Ferris Bueller, a character that he was arguably born to play (seriously, would any other actor have nailed Ferris’ mix of youthful sincerity and boyish charm quite like Broderick did?), he considered a lot of big names for the part.

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These included top ‘80s actors, like Rob Lowe, Michael J. Fox, and John Cusack; future movie stars whose big breaks were right around the corner, like Tom Cruise and Jim Carrey; and even Johnny Depp and Robert Downey, Jr. As great as these actors are, no one but Broderick could play Ferris.

The first cut was two hours and 45 minutes long

The initial cut of Ferris Bueller’s Day Off reportedly clocked in at around 165 minutes (two hours and 45 minutes) long. Movies usually come in a little longer in their first edit, because the editor is just assembling the movie and hasn’t yet trimmed the fat, but 165 minutes is insane. That’s the same runtime as such epics as Boyhood, Django Unchained, and Once Upon a Time in the West. The movie’s eventual runtime was 103 minutes (one hour and 43 minutes), so the filmmakers managed to cut out an entire hour of material and leave behind a coherent movie.

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