Actor John Boyega has said non-white characters were "pushed to the side" by Disney in the last Star Wars film.
The Londoner played Finn in the latest trilogy, which concluded last year.
But he said the film-makers didn't know what to do with his and other diverse characters in The Rise of Skywalker.
"What I would say to Disney is do not bring out a black character, market them to be much more important in the franchise than they are and then have them pushed to the side," he told GQ.
"It's not good. I'll say it straight up."
Image copyright Lucasfilm Image caption The British actor played runaway Stormtrooper FinnWhat else did he say?
Boyega, who In Star Wars Episodes VII, VIII and IX, played a runaway Stormtrooper at Rey's side as a member of the resistance, acknowledged an actor is "not necessarily going to like everything" in a film. He said Star Wars was an "amazing opportunity" and a "stepping stone".
But he vented his displeasure about the storylines in The Rise of Skywalker.
"You guys knew what to do with Daisy Ridley, you knew what to do with Adam Driver, you knew what to do with these other people," he told the magazine.
Ridley's character Rey and Driver, as Kylo Ren, were at the heart of the plot about the fate of the Jedi and the Skywalker dynasty.
Image copyright Lucasfilm Image caption Boyega said the film gave "all the nuance" to Daisy Ridley and Adam DriverBut the film-makers didn't know what do to with Finn or Kelly Marie Tran's character Rose, Boyega said. He also suggested Naomi Ackie, the black British actress who played Jannah, and Guatemalan-born Oscar Isaac, who played Poe, were similarly marginalised.
"What do you want me to say?" Boyega continued. "What they want you to say is, 'I enjoyed being a part of it. It was a great experience...'
"Nah, nah, nah. I'll take that deal when it's a great experience. They gave all the nuance to Adam Driver, all the nuance to Daisy Ridley. Let's be honest. Daisy knows this. Adam knows this. Everybody knows. I'm not exposing anything."
He also spoke about hair stylists who had no experience of working with hair like his but "still had the guts to pretend".
How has Hollywood responded?
Disney has not responded, and nor has director JJ Abrams. But Boyega defended Abrams, who took up the director's chair after Colin Trevorrow departed in 2017, saying: "Everybody needs to leave my boy alone."
There's been no response from any of the main figures in the Star Wars universe - or many others in Hollywood.
Those praising Boyega included Rachel Zegler, who will play Maria in Steven Spielberg's new West Side Story; The Good Place star Jameela Jamil; Matthew A Cherry, who won an Oscar for a short film this year; and British actor Paterson Joseph.
Justice League actor Ray Fisher responded to a fan who asked to hear him and Boyega in conversation.
Fisher has previously alleged a "toxic and abusive work environment" on Justice League, which Warner Bros is reportedly currently investigating.
Boyega also received widespread support from fans and commentators on social media, although others had less sympathy.
Boyega responded to actor and presenter Rapaport.
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