The Farewell opens with a title card declaring that the film is “based on an actual lie” from director Lulu Wang’s own life. That lie is told by a family to their beloved grandmother Nai Nai (Zhao Shuzhen), who has been diagnosed with lung cancer. Told by doctors that Nai Nai has three months to live, the family decides to hide her diagnosis from her and gathers at their home in China to say goodbye under the pretense of a wedding. The film closes with an even more shocking title card: Six years after her diagnosis, Wang’s real Nai Nai is still alive. If Nai Nai was given three months to live, how could that possibly be true?

Somehow, it is. The events dramatized in the movie happened to Wang in 2013. She explored the possibility of turning her life into a film, but when she couldn’t secure enough funding, she instead told her story on an episode of This American Life, which featured interviews with the other members of her family — minus the real Nai Nai, who was still alive, and still clueless about her fatal diagnosis. (Wang told The New York Times no one was too concerned about Nai Nai finding out the truth from This American Life, explaining “They thought it was this niche thing. It’s a very American show.”)

The episode of This American Life drew interest from film producers, and eventually Wang did find the money to make The Farewell. She returned to her hometown in China — and even Nai Nai’s house! — with her cast and crew to shoot the movie there. When Nai Nai visited the set, everyone still had to continue the lie; Wang told the Times that Nai Nai “thought that the movie was loosely based on our family, with everybody coming back to China for a wedding.”

Wang finished the movie and premiered it at the Sundance Film Festival to enormous acclaim. Now The Farewell is opening in theaters around the country — and Nai Nai is still, happily, alive and well, now in her mid-80s. In an interview with Vox, Wang was asked whether her grandmother will see the film. “I don’t know,” she replied. “We got distribution in China. My great-aunt is here [in New York] for the premiere today, so I was asking her what we should do. She’s like, ‘We’ll just tell her that movies are fiction and none of it actually happened. You just made it up for the movie.’”

As for the fact that Nai Nai has outlived her initial diagnoses by more than five years, Wang told The New York Times that her “dad was like, ‘See, we did the right thing!’” Right or wrong, it’s a wonderful feeling when that final title card comes up, and you see the real Nai Nai practicing her tai chi moves.

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