The Hays Code, a set of moral precepts for Hollywood movies during the industry's golden age, forced "Casablanca" to revise its original ending.

Ingrid Bergman and Humphrey Bogart, the stars of 'Casablanca,' bonded over how little they thought of 'Casablanca.'

'Casablanca,' the iconic World War II-era film, was recut for its German release, with all references to the Nazis removed.

The Hays Code limited the ways horror films could scare audiences

Beginning in 1930, the Hays Code laid out a strict set of guidelines for Hollywood filmmakers to prevent films that might corrupt those with a "susceptible mind." That meant no graphic violence, no sexual relations outside of marriage (or of a homosexual nature), and no interracial relationships, among other dictums.

After actress Ingrid Bergman had a child out of wedlock, a Colorado senator proposed granting the government the ability to ban performers deemed morally objectionable.

The most famous line attributed to 'Casablanca'—'Play it again, Sam'—is never said in the movie.

Rob Reiner fell in love while working on the romantic comedy 'When Harry Met Sally...,' inspiring him to change the movie's ending to make it happier.

Explore a critic's list of the best Ingrid Bergman performances, including 'Casablanca,' 'Notorious,' and 'Autumn Sonata.'

Ingrid Bergman left her husband for Italian director Roberto Rossellini, sparking a major scandal in Hollywood's Golden Age.

Watch 'Hearts of Darkness: A Filmmaker's Apocalypse,' the documentary about Francis Ford Coppola's notorious production behind 'Apocalypse Now,' shot by Coppola's wife, Eleanor.

How Alfred Hitchcock changed cinema

In 1960, Alfred Hitchcock changed moviegoing with "Psycho." At a time when audiences came and went during screenings, he enforced strict start times, banned late arrivals, and kept plot details secret. The result? A $32M hit that helped shape modern theater etiquette.

In 1980, Steven Spielberg added a scene depicting the interior of an alien spaceship to a rerelease of 'Close Encounters of the Third Kind' at the studio's request, but later regretted the decision, believing it depleted the movie's enchanting mystery.

The 'Movie Brats'—the nickname given to 1970s film directors like Steven Spielberg, Francis Ford Coppola, George Lucas, and others—ushered in a new era of Hollywood.

The 'golden age' studio system often controlled actors' personal lives

The "Big Five" studio system minted stars, but it also tightly controlled their personal lives. Homosexuality, in particular, was seen as a liability. One example is Rock Hudson, a major star in the 1950s and '60s, who was forced into an arranged marriage with his agent's secretary.

The original ending to 'Rudolph the Red-Nosed Reindeer' was changed after viewers voiced their disappointment

The movie's TV premiere on December, 6, 1964, ended with Santa choosing Rudolph to help him deliver presents across the world. However, young viewers were disappointed that Rudolph never fulfilled his promise to rescue his friends from the Island of Misfit Toys, which he'd promised to do earlier in the film. The producers reworked the ending, correcting the plothole, before the movie was broadcast again in 1965.

Alfred Hitchcock's 1945 film 'Spellbound,' starring Ingrid Bergman, features a surreal scene designed by Salvador Dalí.

Camus was influenced by American culture, especially literature and jazz

He loved the work of writers like William Faulker and Ernest Hemingway, and loved drinking whiskey and listening to jazz. He also admired the actor Humphrey Bogart and his striking performance in the noir classic "The Big Sleep." He was delighted when his wife gave him a Burberry raincoat, thinking it made him look more like Bogart.

The subtle red carpet war

The dress code for the Cannes Film Festival’s red carpet is conservative by today’s standards, leading to conflict with stylists embracing more contemporary looks. While some rules are Cannes’, others are out of their hands because they’re French law.

After a 6-year exile, Ingrid Bergman returned to the US to accept an award for her performance in 'Anastasia.'

Hollywood's 'golden age' was controlled by vertically integrated studios

Hollywood in the early to mid-20th century was largely controlled by the "Big Five" studios: Paramount, Warner Bros., Fox, MGM, and RKO. The studios were vertically integrated, overseeing every aspect of film production, distribution, and exhibition. During this era, actors like Cary Grant and Judy Garland were under contract with specific studios—typically for seven years. Garland signed with MGM at age 13, which counted on them to draw audiences.

Sartre wrote an 8-hour screenplay for a Freud biopic

Sartre was hired to write the screenplay for what would eventually become John Huston's 1962 film "Freud: The Secret Passion," about the life of the psychoanalyst. Sartre, however, had trouble sticking to the parameters of Hollywood. An early draft was estimated to be five hours long. Rather than shortening it, as Huston suggested, Sartre extended it to eight hours and was eventually removed from the production.

Francis Ford Coppola began working on 'The Godfather' to bail his production company out of dire financial straits.

'Bonnie and Clyde,' the 1967 film starring Warren Beatty and Faye Dunaway, was the first major American movie to feature graphic violence.

Director Arthur Penn used the then-new Squibb technology, which triggered realistic and bloody bullet wounds, to portray graphic violence, at the time a taboo in American cinema.

How Audrey Hepburn became a spy during the Nazi occupation

Despite her status as one of Hollywood’s most beloved actresses, Audrey Hepburn experienced a war-torn childhood in Europe that few people know about. During her upbringing in the Netherlands, the Nazi occupation caused Hepburn to quit her life as a ballerina and made her family go hungry. In the face of adversity, Hepburn bravely carried messages for the Dutch resistance. Learn more about the star’s compelling life before finding fame.

Hitchcock created his own archetype with the 'Hitchcock Blonde'

The most iconic Hitchcock Blondes from the director’s catalog include Kim Novak, Ingrid Bergman, and Grace Kelly. The roles they played contributed to the gothic and foreboding aesthetics that have come to be associated with Hitchcock’s work.

10 films that influenced Alfred Hitchcock

Hitchcock influenced generations of filmmakers who came after him, but this article focuses on the films that influenced the master himself. Among the titles on the list are Lyman Howe’s “A Ride on a Runaway Train,” which allegedly inspired the sexually charged ending of “North by Northwest,” and Henri-Georges Clouzot’s “Les Diaboliques,” which many people believe is responsible for the pivotal shower scene from “Psycho.”

Watch Alfred Hitchcock's 1940 film noir, 'Rebecca'

"Rebecca" was Hitchcock's first American film and is the only Hitchcock film to win the Academy Award for best picture. The story, based on a 1938 novel by Daphne du Maurier, is about a widower (played by acting legend Laurence Olivier) and the haunting direction his life takes in her wake.

A number of Hitchcock's most celebrated films are based on novels

Hitchcock’s films are often cited as being literary, and with good reason—many of them are based on works of literature. This list from the Los Angeles Public Library not only names the many novels that were adapted for the screen by Hitchcock, like "Rebecca (1940)," but also provides excellent context for how and why Hitchcock came to make his adaptations.

Hitchcock's 'Psycho' broke many established rules in film

Hitchcock flouted convention for “Psycho,” which many consider his masterwork. Hitchcock broke new ground with the 1960 film, with risqué imagery and shocking twists. The film was the most commercially successful in his long and illustrious career.

Hollywood, explained

It all began in 1887 when Hollywood was registered as a small town before merging with Los Angeles in 1910. Filmmakers moved west to avoid Thomas Edison’s patent lawsuits, and the sunny California climate provided the perfect setting for year-round production. By the 1910s, studios like Paramount and Warner Bros. established themselves, and Hollywood's global dominance was cemented during its golden age from the 1930s to the 1950s.

Ingrid Bergman's first film role was as an extra in the 1932 Swedish film 'Landskamp.'

The Cannes Film Festival was created as a response to fascism

Initially called the International Film Festival, Cannes was created as an alternative to the Venice Film Festival, which French diplomat Philippe Erlanger believed had been politicized by the influence of Hitler and Mussolini.

Woody Guthrie wrote an erotic ode to Ingrid Bergman, which was unearthed years later by Guthrie's daughter.

Camus directed a Picasso-penned play

The show, called "Desire Caught by the Tail," was written by Picasso in 1941 while living in Nazi-occupied Paris. It was first staged in 1944, featuring several French intellectuals, including Albert Camus, who directed, as well as Jean-Paul Sartre and Simone de Beauvoir, who had starring roles.

The board game Risk was created by an Academy Award-winning screenwriter.

'Rear Window' was based on a short story by Cornell Woolrich

Hitchcock's 1954 film, which many consider among the director's greatest, was based on Woolrich's 1942 short story "It Had to Be Murder." The story is characteristic of his dark, claustrophobic work.

Movies that killed these 17 actors' careers

Hollywood's history is checkered with flubs and successes, and many actors have suffered from portraying specific roles, even if the films were successful. This list goes into 17 acting careers that took a nosedive after a specific role, including Elizabeth Berkley in "Showgirls" and Sofia Coppola in "The Godfather: Part III." Read the rest here.

Hollywood movies' ratings are controlled by the Motion Picture Association

The board, established by a board of parents, has provided ratings (like G, PG, PG-13, R, and NC-17) for Hollywood films since 1968. Although the MPA provides specific criteria for rating films, many of the characteristics (such as "snippets of language that go beyond polite conversation") are subjective.

Classic movies are prone to decomposition because they're captured on nitrate film

Nitrate film was the standard in early Hollywood and is prone to decomposition over time. It's led to an estimated 75% of early American films being lost to history.

Spielberg improvised most of the iconic D-Day scene from 'Saving Private Ryan'

Although action sequences are often tightly choreographed, one of cinema's most famous war scenes was mostly shot on the fly. Spielberg wrote seven pages (or approximately seven minutes of screen time) for the scene, though the final cut of the sequence was 25 minutes long.

Hitchcock's career began shortly after World War I

Nearly 60 years after beginning in the silent film era in 1919, Hitchcock produced his last film, "Family Plot," in 1976. Over his decades-long career, Hitchcock brought a literary sensibility to previously maligned genres like thrillers and innovated numerous camera techniques.

'The Jazz Singer,' the first film with synchronized sound, changed Hollywood

Movies changed forever in 1927, when Warner Bros. released "The Jazz Singer," the first feature film with integrated dialogue. Based on a Broadway musical, the movie starred Al Jolson as the son of a Jewish cantor who wants to be a popular singer.

B-movie king Roger Corman mentored many of the star directors of 1970s Hollywood, including Francis Ford Coppola, Martin Scorsese, and Ron Howard.

See Minnelli's iconic performance of 'Maybe This Time' that helped earn her an Oscar

In the film "Cabaret," Minnelli performs the show tune as Sally Bowles, a protagonist embarking on a new love affair in 1930s Berlin. Minnelli's emotive performance and belting vocals helped land her the prestigious acting award.

Steven Spielberg purchased Oscars won by Clark Gable and Bette Davis and donated them back to the Academy

Since 1951, all Oscar statuettes have been awarded with a caveat—if the recipient wants to sell their Oscar, they have to first offer it back to the Academy for the price of $1. As a result, there's now a black market for the golden knights. Some buyers are anonymous movie buffs, but some are the stars themselves.

DH Lawrence's novel 'Lady Chatterley's Lover' was banned for obscenity in numerous countries, but small private printings turned it into an underground sensation in the late 1920s.

Hollywood's efficient response to the Spanish flu made it a filmmaking destination

In 1918, the Great Influenza epidemic killed more than 675,000 Americans. Los Angeles was one of the first cities to shut down movie theaters, most of which were independently owned and couldn’t afford the revenue loss. The results were twofold: the quick response meant that Hollywood could bounce back faster than other film hubs, and it also contributed to the rise of vertical integration as studios stepped in to purchase the flailing theaters.

Disney tried to adapt 'The Catcher in the Rye' for the screen, with plans to reimagine it as an animated film about German shepherds.

Hollywood alternative Flying A Studios was housed in Santa Barbara for a decade

Founded in 1910 in Chicago, the American Film Company moved west to Santa Barbara to shoot cowboy westerns. For a decade, the studio was prolific, putting out an average of 242 films a year but collapsed within a decade due to a lack of vision.

Hitchcock regularly made cameos in his own films

Long before Tarantino was born, Hitchcock was casting himself in his movies’ bit parts, allowing careful audience members to find the director walking through the fictional world he’d created. The history behind that decision was an accident.

The Hollywood sign originally said 'Hollywoodland'

The original sign, which was only intended to be up for 18 months and erected around 1903, advertised a new housing development in the Hollywood Hills. In 1949, the Hollywood Chamber of Commerce shortened it to "Hollywood."