Some people weren't too happy when they found out white actress Tilda Swinton had been cast as the Ancient One, a character normally depicted as an Asian man, in the Marvel's upcoming Doctor Strange movie starring Benedict Cumberbatch.

Among those calling out the movie's creators for "whitewashing"—casting white actors in roles that should go to people of color—was Star Trek actor, social media star and diversity activist George Takei, who dismissed a Doctor Strange screenwriter's previous excuses for the casting choice—arguing that the character would play better in China—as nonsense, saying audiences "should be aware of how dumb and out of touch the studios think we are.​"​

This week, during the film's Los Angeles premiere, director Scott Derrickson addressed the controversy again, saying the choice was actually to prevent a different controversy. From Variety:

"In this case, the stereotype of [the Ancient One] had to be undone. I wanted it to be a woman, a middle-aged woman. Every iteration of that script played by an Asian woman felt like a 'Dragon Lady,'" Derrickson explained, referencing another negative on-screen stereotype of an exotic and domineering Asian woman. "I'm very sensitive to the history of 'Dragon Lady' representation and Anna May Wong films. I moved away from that. Who's the magical, mystical, woman with secrets that could work in this role? I thought Tilda Swinton."

Writer John Spaihts added that the male dominated world of Doctor Strange needed another woman in the mix: "Tilda is an instance of us taking a male role and putting a woman in it ... So we were looking for opportunities to have not only ethnic diversity, but to have gender diversity in the film."

Doctor Strange is set for a Nov. 4 release.