Benedict Cumberbatch skyrocketed to stardom in Sherlock, the BBC's 2010 TV series about a modern-day Sherlock Holmes. The actor leveled up again in 2016's Doctor Strange, playing a slightly different kind of genius in the Marvel Cinematic Universe. Doctor Strange is now one of the biggest heroes in the MCU, having used his powers to mastermind the Avengers' greatest victory ever.

That kind of heroism comes at a price.

Doctor Strange succumbed to one of Hollywood's oldest villains: whitewashing. In the '60s comic, a Tibetan monk guides Strange's magical training. In the 2016 movie, his mentor is instead a Celtic woman played by Tilda Swinton. The recasting came as the lesser of two evils, according to director Scott Derrickson, who said he wanted to avoid Asian stereotypes.

But according to one of the film's writers, there was also the fear of Chinese backlash for any connection to the Tibetan sovereignty dispute, in which China asserts rule over an independence-seeking Tibet.

Marvel/Ian Knighton

Welcome to the murky world of Hollywood self-censoring for China's censorship bodies. These state agencies and party committees decide what plays in the country's theaters, based on a set of broad, changeable guidelines.

Sometimes China's censors object to violent or provocative content. Deadpool, for instance, was deemed so graphically violent that no amount of alterations could save its release, while shaving a few scenes out of Logan was enough to appease censors. The more slippery slope is politics: A movie ensures rejection if it portrays China in a negative light or portrays China's enemies as heroes.

Robert Rodriguez/CNET

The government of China, which monitors the country's population with drones, AI-powered CCTV cameras and internet censorship, allows just 34 foreign films a year, and movie studios will go to major lengths to make the cut. The endgame is unlocking China's treasure chest of box office takings.

"China is an incredibly important movie market and in fact is second only to North America in terms of the amount of revenue that it generates in movie theaters each year," said Paul Dergarabedian, senior analyst at media analytics company Comscore. There would be a "huge void" in the global box office without the money Chinese audiences spend on US blockbusters.

China's box office is sometimes even more important to Hollywood studios than the domestic box office. In 2016, video game adaptation Warcraft avoided bomb status thanks to China's $225 million in revenue, compared to $47 million in the US. In 2017, the eighth Fast and the Furious movie picked up over $100 million more in China than in the US. A year later, a quarter of Aquaman's $1.1 billion global box office washed in from China.

Then there's Disney. It's one of the biggest winners in China: So far this year, the proud owner of Marvel Studios is sitting on more than $1 billion from the country's box office. Avengers: Endgame made $600 million in China, vital to its victory over Avatar as the highest-grossing movie of all time. Avatar, by comparison, made just over $200 million in the People's Republic.

When it came to Doctor Strange, Disney's cinematic diplomacy paid off. The spattering of bad press in the leadup to Doctor Strange's release faded behind the film's $109 million China box office, a sizable chunk of its $677 million global total.

Alberto E. Rodriguez/Getty

Appeasing China's censors is vital to landing a foreign film in the country. South Park creators Matt Stone and Trey Parker emphatically did the opposite with a recent episode designed to annoy China's government. But with huge rewards at stake, it's a game much of Hollywood is eager to play.

In 2021, Marvel will take its focus on China to the next level. Shang-Chi and the Legend of the Ten Rings will be its first Asian superhero movie and part of Phase 4 of the MCU. It seems squarely aimed at China. Chinese-born actor Simu Liu will play the lead role, and the movie will hit theaters Feb. 12, 2021 -- aka Chinese New Year.

But the more closely Marvel targets China, the more carefully it needs to tread.

Why so sensitive?

When it comes to scaling China's firewall, Disney has plenty of experience. Aside from turning Tibetan monks into Celts, the Mouse House opted to have Chris Evans' Captain America enunciate heroically into a Chinese-made Vivo phone, rather than an iPhone from US-based Apple. In the Chinese version of Iron Man 3, with a few extra scenes seen only in the People's Republic, Chinese surgeons save Tony Stark's life.

Marvel

Marvel already knows what Chinese audiences want to see, and what Chinese authorities don't.

"A Chinese producer or co-financer for this particular movie might be helping unofficially," said Matthias Niedenführ, vice director of the China Centre in Tübingen, Germany. Local producers may share story details to Chinese government officers and obtain hints about what the authorities will reject.

Marvel representatives didn't respond to a request for comment on whether Shang-Chi's producers had sought advice from Chinese officials.

Niedenführ also explained that China's sensitivity when it comes to its movie content "is a backlash from a century of perceived oppression from foreign forces. ... National pride is prevalent, and in an environment where a lot of really important topics are taboo, they all can vent frustration over real or perceived offenses against China from foreigners."

MGM discovered China's sensitivity the hard way. Its 2012 remake of alternate-history Cold War film Red Dawn depicted Chinese soldiers as enemies. After unhappy state-run Chinese media got hold of a leaked script, the company spent $1 million digitally editing out any evidence of the soldiers, shuffling in North Koreans instead.

According to Niedenführ, just as China's censors don't want to see Chinese people portrayed as villains, they don't want to see Western colonial powers portrayed as heroes. They also object to "any altering of Chinese historical figures, such as distorting their historical role for China."

Marvel Comics

These existing regulations likely won't be a problem for Shang-Chi, given he's not a historical figure. As long as religious references to Buddhism or Daosim take a back seat, that is.

A sense of national pride, on the other hand, scores a big red tick from the government. Wolf Warrior 2 is the highest-grossing movie in China of all time, beating Avengers: Endgame by $200 million at the domestic box office. The homegrown film, starring martial artist Wu Jing, aka "China's Rambo," follows an ex-special forces soldier as he John Wicks his way through a war zone in Africa to rescue Chinese citizens from Western mercenaries. Its success is pinned on its overt patriotism and for stirring a sense of national pride.

Niedenführ explained that China's market is ripe for Disney's picking, that the Chinese people have been waiting for a Chinese superhero in the MCU. While a Captain China comic exists, so far Asian heroes have played only relatively minor roles in the world's biggest superhero franchise. Actors Chloe Bennett and Ming-Na Wen paved the way for Asian representation in the ensemble TV show Marvel's Agents of S.H.I.E.L.D., but Benedict Wong in Doctor Strange and Jessica Henwick in Iron Fist come second to non-Asian leads.

Disney's casting of a Chinese-born actor in Shang-Chi's lead role is no mistake. But when it comes to the hero's villain, the company is in historically sensitive territory.

Risky business

Shang-Chi's villain in the comics is Fu Manchu. Conceived in 1913 by novelist Sax Rohmer during the Yellow Peril phenomenon, a time in which politicians campaigned to prevent people of Asian descent from entering the US, the walrus-mustached, bald-headed figure is the ultimate reductive Asian stereotype.

Marvel

In the '70s, the character's comic book rights went to Marvel, which turned him into Shang-Chi's villainous father. His inclusion in Shang-Chi the movie would be a guaranteed deal-breaker for China's censors. But his replacement isn't exactly reproach-free.

Hong Kong screen legend Tony Leung Chiu-wai will play The Mandarin, Shang-Chi's antagonist and the mastermind behind dormant terrorist group The Ten Rings. The warrior king, a version of whom featured in Iron Man 3 but was revealed to be an impostor, has kicked up controversy for being a stereotype born in the same period as Fu Manchu.

"If Marvel doesn't want to insult China, change The Mandarin to The English, it's that simple," one Netizen wrote, translated by RADII. Wrote another: "In Europe and the US, it is a known fact that Fu Manchu equals The Mandarin."

In the current political climate, Leung's casting works well for Disney. Pro-democracy protests have turned increasingly violent between Hong Kong activists and police since a bill in April proposed criminal suspects be extradited to mainland China under certain circumstances. When it comes to movies, China may prefer a Hong Kong native in a villainous role.

"It would be more risky if he was a mainland star," said Chris Berry, a professor of film studies in King's College, London. "Casting a Hong Kong star -- even someone as beloved as Tony Leung -- in this orientalist villain role is safer. That's especially true now that everyone in the [China] is looking quite negatively at Hong Kong."

It may be a risk for Marvel to consider China's market from Day 1, to make a move toward the country with a movie that could perform better there than in the US. It's also, according to Berry, "impossible to guess how US audiences will react to" a movie seemingly aimed at Chinese audiences and their lucrative box office.

But for Chinese audiences, Shang-Chi and the Legend of the Ten Rings could be the superhero movie they, and their deep coffers, have been waiting for. And if Disney deftly jumps through China's censorship hoops, as it's managed to do for the past 11 years, Shang-Chi could become one of Hollywood's most valuable heroes.