As seen in Mank, which lands on Netflix on December 4, wunderkind Orson Welles (Tom Burke) hires Mankiewicz—who’s known around the industry simply as “Mank,” per the title—to write the script for what will be Welles’ directorial debut. What Mankiewicz comes up with is a sprawling yet intimate character study that doubles as an indictment of power in America, all famously modeled (conventional wisdom goes) on the life of real-world newspaper tycoon William Randolph Hearst. Welles knows Hearst by reputation, but Mankiewicz knew him personally. Together, writer and director use him as inspiration to bring fictional media mogul Charles Foster Kane to life onscreen.

Fincher’s film floats between scenes of Mankiewicz working tirelessly on the script in a ranch in Victorville, California, and flashbacks to the scribe’s time writing for the Hollywood studio system and trading bon mots with Hearst (Charles Dance) and his inner circle, including actress Marion Davies (Amanda Seyfried). Over the course of two hours, we see how those experiences inform Mankiewicz’s script for Kane.

Regardless of whether people find it to be a worthy companion to Citizen Kane, Mank is sure to be a serious Oscars contender next year. It’s shot in crisp black-and-white, set to period-appropriate sound and filled with rich performances that capture major figures in Hollywood history. That said, the movie’s own screenplay—credited to Fincher’s late father, Jack—is best enjoyed if you’ve got a sense of who all the players are and how they related to one another. Which is why we’ve put together this primer on all of the key characters in Mank.

Herman Mankiewicz (Played by Gary Oldman)

Herman Mankiewicz was described as “the smartest and wittiest guy in the room” by his grandson, TCM host Ben Mankiewicz, during a recent piece on CBS Sunday Morning. (“Also the drunkest,” the younger Mankiewicz added.)

The New York-based journalist was called over to Hollywood in 1926, and became one of the highest-paid screenwriters for Paramount Pictures, and subsequently Metro-Goldwyn-Mayer. By 1936, many of the films he wrote for did not actually credit him. Along with Kane, Mankiewicz worked on 60 other films, including The Wizard of Oz, Man of the World, Dinner at Eight, Pride of the Yankees and The Pride of St. Louis.

During his time on the West Coast, Mankiewicz became good friends with fellow screenwriter Charles Lederer, who was the nephew of Marion Davies, Hearst’s mistress. Mankiewicz was invited to Hearst’s castle in San Simeon several times, and found Hearst to be “a finagling, calculating, machiavellian figure,” as per Richard Meryman’s 1978 book, Mank.

In 1939, after Mankiewicz broke his leg in a horrific car crash, Welles visited him in the hospital with the proposition of writing Citizen Kane, according to Slate. Mankiewicz, whose career was in jeopardy because of his drinking and gambling problems, agreed, and initially signed away his screenwriting credit.

According to The New Yorker, the battle over proper screenwriting credit for Kane began in 1940. Mankiewicz apparently realized that the script was worth having his name on, and appealed to the Screen Writers Guild. He later withdrew his appeal, but RKO ultimately gave Mankiewicz screenwriting credit. Mankiewicz and Welles shared Kane’s screenwriting Oscar, the only Academy Award that the iconic film won.

In the 2004 book The New Biographical Dictionary of Film, David Thomson said of the script: “No one can now deny Herman Mankiewicz credit for the germ, shape, and pointed language of the screenplay.”

Despite the Academy Award he won for Kane, Mankiewicz never worked with Welles again. He continued to write movies, though, and his career experienced an upswing in the wake of Kane, even if he never matched that film’s heights. Mankiewicz died in 1953 of uremic poisoning and kidney failure. He was 55 years old.

William Randolph Hearst (Played by Charles Dance)

Hearst, the newspaper tycoon who built an immense media empire throughout the early 20th century, is widely understood to be the inspiration for Citizen Kane’s titular character. Per Britannica, he entered the media world in the 1890s and became a competitive publisher, owning several newspapers throughout the United States by 1925. During his rise to power, he had a brief political career, but his real influence came from his nearly 30 newspapers and his slew of magazines, along with various production companies and radio stations that he also owned. Hearst was already in the media business for over 30 years when he met Mankiewicz in the early 1930s, according to Meryman’s Mank.

Mankiewicz and his wife were dinner guests at the opulent Hearst Castle several times, according to Slate. Hearst reportedly enjoyed Mankiewicz’s presence and conversation, until Mankiewicz’s alcoholism made him an unwelcome guest at Hearst’s property.

As noted recently by The New Yorker’s Richard Brody, “There’s little doubt, by now, that Mankiewicz’s Hearst connection provided the essential substance for the film; it also nearly destroyed the film before it could be released.” After Hearst heard that aspects of the film were similar to parts of his life, he reportedly forbade his newspapers from featuring ads promoting Kane and tried to paint Welles as a communist, to name just a couple of Hearst’s purported attempts at sabotage.

During the Great Depression, Hearst’s empire began to fail (unrelated to Kane), but it experienced a resurgence during World War II. David Nasaw’s 2000 book The Chief: The Life of William Randolph Hearst also notes that he focused on philanthropy in his later years. Hearst developed an irregular heartbeat in 1947, and doctors demanded he stop working and seek medical attention, which forced him to leave San Simeon for Beverly Hills. He died in 1951 from a heart attack and a stroke at age 88.

Orson Welles (Played by Tom Burke)

In 1939, Orson Welles signed a high-profile contract with RKO Pictures, giving him a remarkable amount of creative freedom, especially for a hotshot upstart in his 20s. Welles was coming off of his legendary 1938 “War of the Worlds” radio broadcast, which famously had some listeners convinced that space invaders had actually touched down in New Jersey. For his first feature-length film, the young auteur set his sights on a picture about a powerful man similar to Hearst, and approached Mankiewicz to work on the script, as per Deadline.

Welles and Mankiewicz apparently had an understanding, when the work began, that Welles would be receiving credit for the screenplay, according to The Hollywood Reporter. But the dynamic between the two seemed to get tense as they got further into the creative process, with Mankiewicz reportedly attempting to get the Writers Guild involved, to recognize him as the film’s only writer. Mankiewicz was eventually awarded credit for the film (top billing credit, above Welles) from RKO Pictures in early 1941.

Mankiewicz’s spite towards Welles intensified for the rest of his life, according to Barton Whaley’s 2005 book, Orson Welles: The Man Who Was Magic. Eventually, though, Welles did note the impact that Mankiewicz had on the film. Decades after making Kane, he said (via Harlan Lebo’s 2016 book, Citizen Kane: A Filmmaker’s Journey), “Without Mank it would have been a totally different picture. It suits my self-esteem to think it might have been almost as good, but I could never have arrived at Citizen Kane as it was without Herman.”

Many feel that Welles peaked with Kane; at the very least, he never again made another movie with as much authoritative control, as noted by The New Yorker. Still, he continued acting in dozens of films, and worked as a director and screenwriter for decades. Welles suffered a fatal heart attack in 1985, at 70 years old.

Marion Davies (Played by Amanda Seyfried)

At the start of Mank, Mankiewicz casually mentions that he knew Marion Davies very well. In real life, they were friends, introduced by Davies’ nephew, screenwriter Charles Lederer.

Davies became Hearst’s mistress after he saw her dancing in the Ziegfeld Follies in New York in 1917, according to The New York Times. The following year, the newspaper mogul created Cosmopolitan Pictures to produce her films, and kept her under a tight, exclusive contract. Hearst used his media empire to promote Davies’ career, reportedly spending $7 million.

Slate notes that Mank is pretty accurate in its depiction of Mankiewicz’s friendship with Davies, since they “bonded over their shared alcoholism.” Mankiewicz’s wife, Sara, apparently insisted that her husband mostly felt sorry for the actress.

Many film audiences and historians believe that Charles Foster Kane’s onscreen mistress, Susan Alexander, was inspired by Davies. According to You Must Remember This host Karina Longworth, Davies claimed that she and Welles never actually saw Citizen Kane.

Throughout her career, Davies acted in over 50 movies, including Lights of Old Broadway (1925), Blondie of the Follies (1932) and Peg O’ My Heart (1933). However, her film career began to wane in later in the 1930s, around the same time as Hearst’s media empire.

During the Depression, Davies had to lend Hearst $1 million to bail him out, according to The New York Times. And after her acting career was long over, Davies devoted her time to help an ailing Hearst. She married not long after Hearst’s death, and then focused on real estate investments and philanthropy. Later in life, Davies was diagnosed with cancer. She died of malignant osteomyelitis (cancer of the jaw) in 1961 at age 64.

Joe Mankiewicz (Played by Tom Pelphrey)

“For many years, (Joe) idolized Herman,” a biographer of the Mankiewicz brothers, Sydney Ladensohn Stern, said recently to Texas Public Radio.

But Joe’s career would ultimately eclipse his brother’s. Joe went to Hollywood in 1929, when Herman secured him a contract at Paramount Pictures, per The New York Times. Ultimately, Joe became a far more distinguished Hollywood presence than Herman, who was 11 years his senior. He was a screenwriter for Paramount, a producer at MGM and eventually directed at Twentieth Century Fox. The younger Mankiewicz worked on dozens of films throughout his career and won four Academy Awards, for writing and directing both A Letter to Three Wives (1949) and All About Eve (1950).

Speaking to TPR, Stern explained that Joe and Herman’s relationship was “complicated.”

“Joe was competitive with Herman, even though he admired him. (But) I don’t think Herman was particularly competing with Joe. When Joe surpassed him, he certainly had mixed feelings, but he was always, also proud of him.”

In 1951, Life ran an article that showed a drastic difference between the two, 10 years after Herman’s success with Kane. “Somewhere along the way,” the article reads (via Los Angeles Review of Books), “the two brothers passed each other, one going up, the other going down.”

Following Herman’s death, Joe continued writing and directing until 1972, according to The New York Times. He died of heart failure days before his 84th birthday, in 1993.

Louis B. Mayer (Played by Arliss Howard)

At one point early into Mank, Mankiewicz says of Mayer, “If I ever go to the electric chair, I’d like him to be sitting on my lap.” This quip was reflective of the poor relationship that Mayer and Mankiewicz had in real life.

In September 1939, while working for MGM, Mankiewicz begged Mayer for advance pay after losing his money while gambling, according to that aforementioned Life article. Mayer agreed, but only if Mankiewicz gave up gambling. The following day, Mayer caught the screenwriter gambling once again; Mankiewicz reportedly left MGM immediately.

Mayer’s biographer, Scott Eyman, noted in his 2005 book, Lion of Hollywood: The Life and Legend of Louis B. Mayer, that Mayer was often compared to Hearst, whom he was friends with. Hearst (who affectionately called Mayer his son), financed the studio executive’s films, while MGM films received rave reviews in Hearst’s newspapers. It was a smart and profitable relationship.

The New Yorker noted recently that Mayer and other studio heads tried to pay off RKO chief George Schaefer to purchase and destroy the negative of Kane. Schaefer refused, but Mayer was successful in getting the studios, which owned the majority of the “first-run movie houses in major cities,” to not run the film. As a result, Kane did not make much of an impact at the box office. Clearly, however, that hasn’t stopped it from living well beyond its initial release.

Mayer was famous for packing his studio with “more stars than there are in heaven,” and dominated Hollywood for decades. Some of the films that came out of his studio under his supervision include Ben-Hur (1925), Fury (1936), The Wizard of Oz (1939), Gone With the Wind (1939), The Philadelphia Story (1941) and An American in Paris (1951). Perhaps his greatest contribution to the world of cinema is thought to be MGM’s movie musicals, Eyman noted, which grew in popularity in the 1940s and 1950s. Following World War II, Mayer’s studio began a slow decline, as audiences wanted more sophisticated plots than the sentimental films that MGM offered.

According to The New York Times, Mayer resigned from the studio in 1951, and died in 1957 of leukemia, leaving behind an enduring legacy. The Golden Age of Hollywood would not have been the same without Mayer. As Eyman probably put it, “Louis B. Mayer defined MGM, just as MGM defined Hollywood, and Hollywood defined America.”

Irving Thalberg (Played by Ferdinand Kingsley)

Another Boy Wonder of sorts, Irving Thalberg was a producer during the early years of Hollywood. At the young age of 20, he was hired to oversee production at Universal Studios in Los Angeles. Three years later, Thalberg was invited for a meeting with studio head Louis B. Mayer. After their meeting, according to Karina Longworth, Mayer called Thalberg’s lawyer, saying: “Tell him if he comes to work for me, I’ll look after him like my own son.” He then hired Thalberg as vice president and head of production at a film company that eventually became Metro-Goldwyn-Mayer, according to the Academy of Motion Picture Arts and Sciences.

Thalberg was bright, wildly successful, and a workaholic who suffered a heart attack at a very young age, according to a 1933 article published in The Hollywood Reporter. He had a history of poor health, and doctors told him that he wouldn’t make it past the age of 30, according to Britannica. Despite this, he worked long days and mingled with the stars all night.

Thalberg and his wife were friends of Hearst, and were invited over for dinner parties. Hearst pushed for Davies to be in the 1938 film Marie Antoinette, which Thalberg produced, according to Slate. The producer resisted, and cast his wife, actress Norma Shearer, instead. Hearst reacted by pulling Davies from MGM, and moving her to Warner Bros. in 1935.

The young producer also dabbled in politics. As noted by Slate, Thalberg produced a series of fake newsreels to help tip California’s 1934 gubernatorial election in favor of Republican Frank Merriam, and away from author Upton Sinclair, who was running as a Democrat. Mank’s story hinges on the staged newsreels, in a way: In the film, Mankiewicz discovers that the reels—which feature bogus testimonials and interviews designed to make Sinclair look like the candidate of lower-class folks angling for a handout—are being put together by Thalberg and funded by Hearst. The way Fincher tells it, seeing what some people will do to cling to power stays with Mankiewicz, and eventually colors his script for Citizen Kane.

Slate points out, though, that while Thalberg did actually produce such material, it’s not clear if Mankiewicz was appalled by the newsreels, or if he was moved in part to write Kane because of them.

Thalberg died in 1936, after he caught pneumonia. He was 37, according to The Los Angeles Times.

Rita Alexander (Played by Lily Collins)

In critic Pauline Kael’s famous 1971 New Yorker essay “Raising Kane,” about the writing of Citizen Kane and Mankiewicz’s authorship (which itself was no doubt an influence on Mank), it’s said that Rita Alexander “took dictation from Mankiewicz, from the first paragraph to the last,” while the screenwriter recovered from his 1939 car crash.

Not too much is known about Alexander, compared to the other principal figures in Mank, but she apparently served as some sort of inspiration to Mankiewicz. Barton Whaley’s Orson Welles: The Man Who Was Magic, notes that Mankiewicz paid homage to her by naming Kane’s mistress after her: Susan Alexander Kane. That might not necessarily seem all that flattering, since Susan Alexander Kane is a tragic alcoholic in Citizen Kane, but, hey, having a character in one of the greatest films of all time named after you should be considered an honor. Think of it as her very own credit.