Terry Gilliam's 1998 film Fear and Loathing in Las Vegas is one of the most beloved comedies of the '90s. Based on the novel of the same name by Gonzo journalist Hunter S. Thompson, the story follows drugged-out writer Raoul Duke (Johnny Depp) and his equally inebriated lawyer Dr. Gonzo (Benicio Del Toro), who are tasked with covering a motorcycle race in the desert outside of Sin City.

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Fear and Loathing in Las Vegas opened in the U.S. on May 22, 1998. Although the film scored middling reviews, the movie was a bomb at the box-office, earning $10.6 million in worldwide grosses against an $18.5 million budget. For more, here are ten things you never knew about Terry Gilliam's Fear and Loathing in Las Vegas.

The Novel Caught Many Filmmakers' Attentions

Fear and Loathing in Las Vegas

Hunter S. Thompson's novel Fear and Loathing in Las Vegas was originally published in 1971. Since then, several Hollywood attempts to adapt it to the big-screen occurred prior to Terry Gilliam's involvement, including many high-profile stars and filmmakers.

Martin Scorsese and Oliver Stone tried to do so at various points, while stars Jack Nicholson and Marlon Brando were in talks to star as Duke and Gonzo respectively but became too old for consideration. Dan Aykroyd and John Belushi were considered until the latter's untimely death. John Malkovich and John Cusack were later considered for the role of Duke. It wasn't until Thomspon personally met Johnny Depp that he felt no one else but he could play Duke.

Johnny Depp Wanted Bruce Robinson To Direct

Bruce Robinson and Johnny Depp

When Johnny Depp was initially attached to the film, he sought acclaimed English filmmaker Bruce Robinson to direct. Depp was taken with Robinson after seeing his coming-of-age film Withnail and I.

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Robinson declined the offer, claiming the novel too difficult to film. However, Robinson agreed to direct the adaptation of Hunter S. Thompson's first novel, The Rum Diary, in 2011, also starring Johnny Depp as the gonzo journalist.

Johnny Depp Became Friends With Hunter S. Thompson

Hunter S. Thompson shaves Johnny Depp

Johnny Depp and Hunter S. Thompson became fast friends while making the film. It was Thompson who shaved Johnny Depp's head for the role, conducting the haircut in Thompson's kitchen while using the light from a miner's hardhat to see properly. The two men even traded cars prior to filming.

Moreover, Depp spent four months with Thompson in preparation for the role of the writer's gonzo alter ego. Several of Duke's costumes in the movie came from Thompson's own wardrobe. Although Thompson approved of Depp's performance, he admitted that if he ever saw someone acting exactly the way Duke did, he'd hit them with a chair.

Bill Murray Gave Some Acting Advice To Johnny Depp

Bill Murray in Where The Buffalo Roam

In 1980, Bill Murray portrayed Hunter S. Thompson in the movie Where the Buffalo Roam, which was also based on Fear and Loathing but received less praise and attention. Murray also worked with Depp on Ed Wood four years prior to Fear and Loathing Las Vegas, and gave the star a word of advice prior to portraying Thompson onscreen.

Murray advised Depp to be careful, or else he'd find himself playing the wacky character for the next ten years. Murray also told Depp to make sure his next starring film role was as far from Thompson as possible to avoid being pigeonholed. He took this advice seriously, as seen in his next roles in The Ninth Gate and The Astronaut's Wife being noticeably more somber than Duke on a slow day.

Tobey Maguire's Bald Look Cost $15,000

Fear and Loathing in Las Vegas

One of the most memorable scenes in the film involves Duke and Gonzo picking up a hitchhiker (Tobey Maguire) en route to Vegas. Due to reshoots months later, a glaring inconsistency with Magure's hairline can be spotted.

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On the Criterion Collection DVD commentary, Gilliam explains that Maguire's drastically altered hair in the scene is due to reshooting the sequence several months later. Thanks to a clause in Maguire's contract, it would have cost $15,000 to shave his head before applying the wig. Since the movie was already going over budget, Gilliam decided not to shave Maguire's head. Still, the cost of using a bald-cap and digitally erasing Maguire's hairline in postproduction ended up costing well over $15,000.

The Film Features Some Cameos

Hunter S. Thompson sits at a table from Fear and Loathing In Las Vegas

Director Terry Gilliam makes a cameo appearance in the film as the motorcycle race announcer/director in the desert. He can be wearing a baseball cap and holding a microphone as the racers take off.

Elsewhere, Hunter S. Thompson also makes a meta-cameo in the film. When Duke is stumbling through the Jefferson Airplane concert, he looks directly at Hunter S. Thompson and says "there I was...Mother of God...there I am!" Also, producer Laila Nabulsi appears as Grace Slick, lead singer of Jefferson Airplane.

Benicio Del Toro Gained Weight For His Role

Benicio del Toro in Fear and Loathing in Las Vegas

Benicio del Toro's role of Dr. Gonzo is based on Thompson's longtime friend, Oscar Zeta Acosta, who purportedly drowned to death in 1974. In preparation for his performance, Del Toro gained 40 pounds. According to the Criterion Collection DVD commentary, del Toro ate multiple donuts a day to put on the weight.

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The star of Sicario also improvised the scene at the beginning of the movie when Gonzo accidentally spills the vial of cocaine. The part where Del Toro licks the cocaine remnants off of the suitcase was not scripted.

Ralph Steadman's Recurring Cactus

The main characters looking around in their car in Fear and Loathing in Las Vegas.

Eagle-eyed fans of the film may notice a recurring visual motif involving a trippy-looking cactus. When Duke begins to see a swarm of bats at the beginning of the film, he pulls the car to the side of the road. In the background, a bizarre cactus makes its first of several background appearances.

According to Gilliam on the Criterion commentary, the cactus was designed by Ralph Steadman, illustrator of Thompson's original novel on which the film is based. Gilliam resented the prop for how heavy it was to constantly carry around the set.

Bazooko Circus Casino Was Based On A Real Establishment

Bazooka Circus Casino

The Bazooko Circus Casino seen in the film was directly patterned after the Circus Circus hotel and casino in Las Vegas, which appears in the novel. The large gorilla statue that adorns the entrance of the casino now resides in Johnny Depp's front yard.

During production, Circus Circus wanted nothing to do with the film and rejected use of its namesake. Still, the exteriors and interiors (filmed in the now-defunct Boardwalk Casino) were modeled after Circus Circus, including the carousel-themed bar.

Terry Gilliam Originally Didn't Get Writer's Credit For His Script

Terry Gillam directs Fear and Loathing in Las Vegas

Terry Gilliam replaced director Alex Cox (Repo Man, Sid & Nancy) after production was already underway. Cox left over creative differences, prompting Gilliam to rewrite the script in a few short days to accommodate his visual style.

Gilliam co-wrote the script with Toni Grisoni, both of whom became involved in a dramatic Writers Guild dispute. Gilliam and Grisoni's screenplay was deemed too similar to a script adaptation of Thompson's novel written earlier by Alex Cox and Tod Davies. As such, Gilliam and Grisoni were stripped of a screenwriting credit. This prompted Gilliam to burn his WGA card at a public book signing, which in turn resulted in Gilliam and Grisoni receiving a writer's credit on the film.

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