You may already know your favorite moments from Caddyshack, which turns 40 years old today, by heart. But after reading this list, you’ll be a lock for membership at Bushwood Country Club.

1. Caddyshack got made because of Animal House.

Caddyshack director and co-writer Harold Ramis was also a co-writer of the 1978 National Lampoon comedy classic Animal House, along with eventual Caddyshack co-writer and producer Douglas Kenney. Held to only a $3 million budget, their film of frat-house shenanigans went on to gross $141 million at the box office.

You would think that box office success would afford the filmmakers carte-blanche privileges for any follow-up project, but that wasn't the case. Ramis pitched two ideas to Orion Pictures (the now-defunct production company that would go on to make Caddyshack): One was a dark satirical comedy about the American Nazi Party in Skokie, Illinois, and the other was what Ramis dubbed a “revisionist Marxist western.” Both ideas were swiftly rejected, but another idea—a comedy about caddies at a country club, pitched by Kenney and co-writer Brian Doyle-Murray as “Animal House on a golf course”—was given an immediate green light.

2. The screenwriting process for Caddyshack was (almost) entirely autobiographical.

To write their screenplay, Ramis, Kenney, and Doyle-Murray locked themselves in a room and tried to recall everything they knew about or experienced at golf courses and country clubs growing up—most of which came from Doyle-Murray, who caddied at Indian Hill Country Club in the suburbs of Chicago as a kid.

Doyle-Murray's sizeable Irish Catholic family even served as the inspiration for scenes and characters in the film. His brother Bill played head greensman Carl Spackler. Memories of living with their eight other siblings (including three sisters) inspired the opening scenes with main character Danny Noonan’s overcrowded house of siblings. Danny, who sets out to win the caddy tournament scholarship, was based on Doyle-Murray’s older brother Ed, who won a similar prize when he was young. The lumberyard that employs Danny is borrowed from the real life of Doyle-Murray’s father, who was an executive at J.J. Barney Lumber Company. The infamous "Baby Ruth in the pool" scene was culled from the Murray kids' real-life high school exploits.

Ramis drew from real-life experience while writing as well. He admittedly had only played golf twice in his life before directing the film, and recalled that he nailed someone in the nether regions with one of his first practice shots taken to prepare for the film. Naturally, he made use of this tale by contributing the scene where Judge Smails (played by Ted Knight) gets hit in the crotch with an errant golf ball.

3. The studio wouldn’t make Caddyshack unless they got a star.

Chevy Chase in Caddyshack (1980). Warner Home Video

The finished Caddyshack script was a whopping 250 pages in length, more than double the average screenplay. Studio bosses immediately demanded that it be cut down, and added a second stipulation: No star, no movie. First-time director Ramis offered them three, though the first two were untested as far as the studio was concerned.

The filmmakers originally envisioned actor Don Rickles as the slobbish condo magnate Al Czervik, but they settled on comedian Rodney Dangerfield, who'd garnered success in comedy circles and on The Tonight Show with Johnny Carson. Caddyshack would be his first big feature film. Bill Murray was fresh off of three years at Saturday Night Live and had appeared in Meatballs (co-written by Ramis) and Where the Buffalo Roam. The studio finally went ahead when Ramis and company secured Chevy Chase to portray the film's pompous-but-well-meaning playboy Ty Webb (whom they had written the part for anyway, unbeknownst to the studio).

Chase was the biggest catch of the three, having received a Best Actor Golden Globe nomination for the 1979 box-office hit Foul Play. Ramis had Mickey Rourke in mind for the leading role of Danny Noonan, but felt that he couldn't convincingly portray the "goofy kid-next-door." Filmmakers ultimately settled on actor Michael O’Keefe.

4. Caddyshack director Harold Ramis didn’t know what he was doing.

Director Harold Ramis Getty Images

By 1980, Harold Ramis was already a comedy heavyweight, having garnered success live (with the Second City comedy troupe), on the radio (the National Lampoon Radio Hour), and on television (SCTV). He'd also co-written Meatballs and Animal House, but Caddyshack marked his first attempt at directing. Conflicting accounts from cast and crew say that Ramis looked through the camera lens instead of the viewfinder on the first day, and also mistakenly called out “Cut!” instead of “Action!” on early takes. The veracity of these jokes is uncertain, but it is true that the studio was so skeptical of Ramis's abilities that they asked associate producer Don MacDonald to submit a list of directors who could be quickly brought in as on-the-fly replacements, if needed. Luckily, Ramis figured things out, later directing such comedy classics as National Lampoon’s Vacation and Groundhog Day.

5. Caddyshack's filmmakers got out of L.A. to avoid problems, but found new ones.

Orion Pictures wanted the production to be filmed in Los Angeles, but Ramis knew things would be better out from under the thumb of studio execs. He convinced the studio to look elsewhere, since the Illinois setting of the fictional Bushwood Country Club wouldn't include Southern California's palm trees. But the chosen site was Rolling Hills Country Club (now Grande Oaks) in Davie, Florida—which had palm trees! Rolling Hills was one of the few golf courses away from L.A. that would allow the production of a movie on its grounds.

Production was held up both completely (by Hurricane David) and sporadically (by the noise from flights leaving and entering nearby Fort Lauderdale-Hollywood International Airport). The cast and crew took advantage of the hurricane delay by holding a huge indoor party at their hotel next to the country club.

6. Rodney Dangerfield’s audition for Caddyshack was unorthodox, and on set, he felt that he got no respect.

Prior to Caddyshack, Dangerfield was known primarily as a comic from his appearances on The Ed Sullivan Show, The Dean Martin Show, and The Tonight Show (he appeared a total of 36 times). Caddyshack marked Dangerfield's first big-time appearance on the silver screen. For his audition, the comic allegedly arrived at executive producer Jon Peters's office in a black stretch limosine, wearing a long black trench coat with a cheap leisure suit underneath. When it was time for him to audition, he walked into the room, removed his pants, and said, “Let’s eat!” He won the role of nouveau-riche bigmouth Al Czervik, but became nervous whenever he turned on his personality in front of the camera. When actor Scott Colomby (slick caddy antagonist Tony D’Annunzio) asked Dangerfield about his struggles, Rodney allegedly said that he was bombing because nobody was laughing at his jokes. Colomby reassured the rookie actor that if they laughed they’d ruin the take.

7. Bill Murray showed up for six days of filming on Caddyshack and made comedy history.

As a youngster, Bill Murray was a groundskeeper, a caddy, and even ran a hot dog stand at the Indian Hill Country Club, the location that inspired the Illinois setting of the film. At first, Murray's appearance as oafish groundskeeper Carl Spackler was planned as a quick cameo, but his characterization was so funny that Ramis requested he stick with the production a bit longer. Murray filmed for a total of six days, and all of his lines—including his Dalai Lama speech—were improvised on-the-spot. In fact, the only script direction for what became his "Cinderella speech" read: “Carl cuts off the tops of flowers with a grass whip.” Murray took it from there and ad-libbed lines that would, in 2005, be named to the AFI's list of greatest movie quotes of all time.

8. Harold Ramis cast an actor from the Golden Age of Hollywood in Caddyshack, and poked fun at his career in a clever way.

Actor Henry Wilcoxon plays the unassuming but hilarious role of Bishop Pickering—and it was the last film he made before he passed away in 1984. The actor had been involved in some of Hollywood's biggest epics: His stage and screen career reached back all the way to a role in 1931’s The Perfect Lady, and included roles in 1941's That Hamilton Woman and 1942's Mrs. Miniver, which won an Oscar for Best Picture.

Historically, Wilcoxon is best known for his collaborations with legendary director Cecil B. DeMille. Wilcoxon played Marc Antony in DeMille’s Cleopatra in 1934, Richard the Lion-Hearted in 1935’s The Crusades, and was in The Greatest Show on Earth—another Best Picture winner—in 1952. In his Caddyshack scene, Wilcoxon is struck by lightning after shouting "Rat farts!" when he missed a putt to end what would have been the best golf game of his life. Ramis knowingly added in a music cue from DeMille’s film The Ten Commandments. Wilcoxon appears in that film as well, playing Pentaur.

9. Caddyshack's Zen golf techniques came from co-writer-producer Douglas Kenney.

The idea for Ty Webb quoting 17th-century Japanese poet Bashō and using Zen philosophy to better his golf score came from Kenney’s personal experimentation with Buddhist meditation and enlightenment. According to Doyle-Murray, Kenney “had an idea for a putter with electromagnetic sensors that would signal you to putt when you'd reach alpha state." Later, when the filmmakers wanted Ty Webb to make some sort of Zen sound, and Kenney wasn’t around to advise them, Ramis just gave Chevy Chase one direction: “Make a spiritual sounding sound.” Chase improvised Webb’s hilarious “Na-na-na-na-na” putting sound on the spot.

Caddyshack wasn't the only time the writer infused his projects with Zen; he tried to make a few movies about the topic. One rejected pitch was a comedy about Zen Buddhists in the Himalayas fighting the Red Chinese. He also tried to produce a film adaptation of the book Zen and the Art of Motorcycle Maintenance before his accidental death in 1980, just a month after Caddyshack hit theaters.

10. Caddyshack evolved into something other than “Animal House on a golf course,” and employed a classic comedy trio for inspiration.

Ramis filmed scripted scenes of Danny and the caddies running wild at the country club, believing that his scenes with Tony D’Annunzio and Maggie O'Hooligan would form the main core of the story. But viewing the dailies after a few days of shooting, Ramis realized that the scenes featuring the golfers were too essential to let go. This forced Ramis and his co-screenwriters to reconfigure the narrative focus of the coming-of-age story about Danny into a broader comedic view of the country club itself, based around the hilarious vignettes involving Murray, Dangerfield, and Chase. Ramis would now conduct Caddyshack as if it were a Marx Brothers film. According to Ramis, he thought of Dangerfield as Groucho, Murray as Harpo, and Chase as Chico.

11. Caddyshack's introduction scene between Bill Murray and Chevy Chase was based on the contents of a studio note.

The original script for Caddyshack did not include a scene where Carl Spackler and Ty Webb meet, so the studio sent Ramis a note requesting that he take advantage of the talent and come up with a funny scene for Murray and Chase. Some on the set were skeptical of the outcome, thanks to some bad blood between the two after Murray replaced Chase on SNL.

Ramis, Murray, and Chase met to discuss things when production broke for lunch, and they worked together to come up with an outline of a scene where Ty stumbles into Carl’s shed, and the two talk about Carl's rather unique strain of grass, which can be used both on golf courses and to smoke like marijuana. Like much of the comedic bits from the film, the scene was ultimately improvised by the SNL alums and was shot without incident. Murray would later talk about a fight that broke out between the two when Chase returned to co-host SNL while Murray was still on the cast, saying "It was kind of a non-event. It was just the significance of it. It was an Oedipal thing, a rupture.”

12. The Gopher wasn’t originally a big part of Caddyshack.

When shooting concluded in September 1979, Ramis and editor William Carruth had a lot of footage to work with. With so much plot and so many jokes, their first rough cut of the film ran 4.5 hours long. They had already decided to abandon Danny as the main focal point in favor of the comedic heavyweights in Murray, Dangerfield, Chase, and Knight. Still, the filmmakers felt that they needed something to package the film and make the story more coherent. Executive producer Jon Peters suggested, on a whim, that they increase the role of the gopher, turning it into the narrative through-line that tied the film's bits together. The only problem? They didn’t really have a gopher.

During filming, Murray acted his scenes “hunting” the gopher by himself, and the only scene they shot with him trying to catch it involved a hand puppet made out of mink fur. (This cheap puppet can also be seen in the scene where Dangerfield yells “Hey, that kangaroo stole my ball!”)

Ramis looked into bringing in a live, trained gopher to act out the scenes, but Peters weasled some extra money out of the studio and tasked special effects supervisor John Dykstra (an Oscar-winning FX master who had worked on on Star Wars) to create a believable gopher puppet. This explains why Murray and the dancing rodent never appear together onscreen—the scenes in the gopher holes were shot by Dykstra after principal photography had concluded, and were cleverly stitched in to make the scenes appear seamless. The sound effects used for the gopher were the same sounds used for the dolphin in the 1960s TV series Flipper.

13. The owners of the country club where Caddyshack was shot were not happy about the explosions on the golf course.

The climactic scene of Murray’s gopher-killing plastic explosives knocking in Danny’s putt to win the unfriendly wager between Al Czervik (Dangerfield) and Judge Smails (Knight) were real pyrotechnics set aflame at Rolling Hills. To pull off the effect, an artificial green was rigged with several incendiary packs and put into place between two fairways.

This was news to the owners of the country club, who had made it clear to filmmakers that the outrageous climax couldn't be shot anywhere near their golf course. To get them to “comply,” producer Jon Peters invited them out for a swanky lunch away from the country club to “thank them for letting the film use the location.” Ramis then had the special effects crew blow up the fake green while they were away. The fireball from the explosion was so large that a pilot landing a plane at nearby Fort Lauderdale-Hollywood International Airport radioed in to air traffic control that he thought he might have witnessed a crash.

14. Harold Ramis made some unusual choices for the songs in Caddyshack.

As the 1980s began, it seemed like every movie was accompanied by a custom theme song or a catchy pop single, and Caddyshack was no different. But Harold Ramis’ first choice for the artist behind that song was a little unorthodox for the type of silly comedy he was making. The director first approached Pink Floyd—who had just released their sprawling concept double-album The Wall—to come up with a song to play over the film's opening and closing credits. The band politely declined, and soft rock icon Kenny Loggins stepped in to provide the song “I’m Alright” for the film. Loggins would go on to find additional soundtrack fame with 1986’s “Danger Zone” from the film Top Gun.

15. You can experience Caddyshack yourself at the Murray Bros. Caddyshack Restaurant.

On June 7, 2001, all six Murray brothers (Ed, Brian, Bill, Andy, John, and Joel) opened a Caddyshack-themed restaurant at the World Golf Village in St. Augustine, Florida. Designed to “look and feel like a country club gone awry,” the restaurant's menu includes a Double Bogey Cheeseburger, Pulled Pork Sandwedge, and the CaddyShake. Wall displays provide pictures and quotes from the film, and hidden gophers litter the décor. It's said that Bill Murray even stops in from time to time to sing a little karaoke.

Additional Source: Caddyshack DVD commentary