"This is the biggest gathering of cultural appropriators in history," Sacha Baron Cohen tells the camera in his parody of a street accent.

Behind him, hundreds of fans cram onto a London Underground escalator, all wearing Ali G's trademark yellow shell suit and skullcap. Baron Cohen shouts the character's catchphrases through a megaphone, with the crowd enthusiastically finishing each one.

Earlier this month, more than 300 fans attended an official Ali G lookalike competition, ferried around London on an open-top bus that stopped at landmarks including Big Ben, Leicester Square and Covent Garden.

The stunt was promotion for an upcoming sequel to 2002 film Ali G Indahouse - called Ali G: Who iz I? - which hits cinemas on Friday.

But not everyone is excited about the return of Baron Cohen's comedy character.

Critics have long accused the actor of perpetuating racial stereotypes with Ali G, and criticism of the upcoming sequel has gained traction online, with social media posts from comedians, content creators and film fans attracting thousands of likes and comments.

And last month, discussing the film's trailer on the Jeremy Vine show, Labour MP Paulette Hamilton called the character racist. She said she believed Baron Cohen would not get away with portraying any other racial group "in the way he has done with the black community".

Baron Cohen acknowledged an inevitable backlash when he first announced the sequel, writing on X: "In an age where a comedian's career can be ended by a single un-PC joke, I thought I'd play it safe and bring this guy back."

Recently, he shared a video posted to a newly created Instagram account, in which a grey-haired academic urged viewers to boycott the upcoming film. The character appeared to be Baron Cohen in prosthetic make-up.

Has Ali G passed his sell-by date? Or are racial stereotypes, and those who believe them, the true butt of the joke?

Alternatively, as some critics argue, is the whole thing simply not very funny?

The character of Ali G rose to fame through a series of deadpan TV interviews with figures including Harrods owner Mohamed Al Fayed and the Beckhams, from which catchphrases such as "Booyakasha" and "Is it because I is black?" entered popular culture.

But some critics say these catchphrases have since been appropriated by others in a real-life context to mock black people and dismiss their concerns.

Comedian Dane Baptiste, the first black British comic nominated for an Edinburgh Comedy Award, remembers hearing Ali G catchphrases everywhere during the character's noughties heyday. "A lot of the time, I would hear people using phrases like 'Is it because I is black?' or 'Booyakasha'," he recalls.

"Even taking the phrase 'Is it because I is black?'... that was used to the point of caricature, whereby, whenever black people experienced actual grievances relating to systemic and institutional racism, it was reduced to this catchphrase."

Baptiste believes the character, which he calls a "black caricature", is returning at a time when black creatives are being "starved of opportunities".

The controversy around Ali G is not new. When the Ali G Indahouse movie was released in 2002, protesters gathered at its Leicester Square premiere and organiser Peter Akinti branded the character the "new Al Jolson", a 1920s entertainer who used to perform in blackface.

Little is known about the plot of the Ali G sequel beyond the character discovering his girlfriend Julie is pregnant and travelling to America to interview a slew of unsuspecting real-world participants, including American physicist Alan Lightman and retired Army General C Stewart Rodeheaver, who appears in the film's trailer.

When Ali G first arrived on our screens, characters like him were far more common, says social psychologist Amy Kean. She argues they are no longer "culturally relevant".

"Ali G, Little Britain, Catherine Tate, all of those comedians and sketch shows, they made the voice the joke," says Kean, who has written on accentism, drawing from her experiences being teased for her Essex accent.

"I remember going to school in the 90s and people would take the piss out of anyone whose voice wasn't exactly the same as everyone else's."

Baron Cohen has in the past suggested that his character had a knack for pushing powerful interviewees into uncomfortable territory by playing with biases and expectations.

Speaking on The Late Show with Stephen Colbert in 2020, Baron Cohen reflected on interviewing Donald Trump for Da Ali G Show, and recalled how the programme's producer was a well-spoken Englishman who Trump had assumed would be conducting the interview.

"I remember Donald Trump looking at me, and I'm wearing a sweatsuit," Baron Cohen said. "His face dropped. He was immediately furious that he was going to have to speak to somebody from a lower-class borough rather than this rather astute Etonian producer."

When discussing the forthcoming sequel on CBS on Tuesday, Baron Cohen's "primary objective" appeared less ideological - to "get people to laugh really hard". Though he added that "smuggled in there is a bit of satire".

In a new essay in Time this week, Baron Cohen argued that his characters have always been "vehicles to expose prejudice, bias, and stupidity", and that in the case of Ali G, "the joke is on him, and on the predominantly white male establishment" he aims to expose.

"The fact that Ali G is outdated and problematic is the very reason I resurrected him," Baron Cohen wrote.

"The world he's returned to is, in many ways, worse than the one he left 20 years ago. All the prejudices my characters are designed to expose haven't just lingered - they've metastasized. They're fueled by the greatest propaganda machine in history - social media - and now by its monstrous child, AI."

The actor is no stranger to putting himself in potentially dangerous situations for his comedy. In a previous film, he infiltrated a gun rally, disguised as a "right-wing singer", while secretly wearing a bulletproof vest.

Once members of the crowd realised they were being mocked, Baron Cohen was escorted into a getaway vehicle as an angry crowd "started pounding on the vehicle with their fists".

Judging by Baron Cohen's description of the upcoming film, there may be further potential for danger. He told CBS he wanted to examine "conspiracies and lies" and test whether "we, in a matter of hours, could turn intelligent people who believed in the theory of race replacement into murderers".

Colton Dunn, one of the film's black writers, questioned why Baron Cohen would put himself in danger, where interview subjects might react violently, if his intentions were racist.

"From my point of view, Ali G is not a racist character. Ali G is a tool to expose racists," Dunn told Deadline.

"That's why I signed on. I wouldn't sign on to work with somebody that I thought was racist, that's against everything that I've done," he added.

Almost 25 years on, Ali G still has loyal fans - including in his "home town" of Staines, in Surrey.

Staines-upon-Thames resident Alex Balkan, who campaigned for a statue of Ali G in the town, says the character remains a source of local pride.

While acknowledging not everyone welcomes the proposal, he says Ali G put Staines on the map.

"Everyone knows about us because of Ali G, and many of us wear that as a badge of pride," he says. "It's a great conversation starter. It feels nice that people know about your town."

Asked about accusations of racial stereotyping, Balkan believes the character is designed to be seen as a white man attempting to put on a stereotypical gangster persona, rather than to poke fun at black culture itself.

One of the character's defenders is one of his most famous prank victims, politician Sir Jacob Rees-Mogg.

"It is clever, satirical humour which makes the country, and many of us look foolish, and that's no bad thing," Sir Jacob posted on his social media.

While some argue that audiences may have moved on from Ali G, supporters of the character contend that objections to his return reflect growing concerns about creative freedom in comedy. Balkan goes further, arguing that people today are more easily offended than they were two decades ago.

"This excessive zeal of political correctness, of left-wing po-facery, is crazy," Sir Jacob said. "It's a joke, it's comedy and it is poking fun at society as it is, as the best comedy often does."

It would be unwise to judge the film before audiences have seen it. But the controversy surrounding its release suggests that, more than two decades after Ali G first appeared, the debate over who exactly is being laughed at is far from settled.

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