It was a single image that drew documentary filmmaker Yunah Hong toward the life of Hollywood actress Anna May Wong.
In it, Wong is still 17 years old, the year is 1922, and she is staring back boldly at the camera.
"What struck me immediately was how ordinary she looked," says Hong. "I thought to myself, how did this girl become such a star? But you can see something there in her eyes.
"It has been 50 years since she died and no Asian woman has ever done what she did. And still, the world doesn't know that much about her."
Hong's documentary, "Anna May Wong: In Her Own Words", has made its world premiere at the 15th Pusan International Film Festival (PIFF) - Asia's most prestigious cinema event.
It provides a fascinating and often poignant insight into a Chinese-American woman who was, as history has shown, way ahead of her time.
Born Wong Liu Tsong, the daughter of a Los Angeles Chinatown laundry man, Wong made her first film at 17 - the silent classic "The Toll of the Sea" - went on to star in around 50 films over 20 years.
She played alongside stars from Douglas Fairbanks ("The Thief of Bagdad") to Marlene Dietrich ("Shanghai Express"). She also toured the globe with a cabaret act she had devised to showcase her own talents.
Wong was, according to newspaper reports of the time, a sensation in Berlin, London and Paris in the 20s and 30s but racist policies in Hollywood meant she was denied the roles she ached for.
After years of heavy drinking, she died alone in Los Angeles of a heart attack in 1961, aged 56.
"Her career was pretty much over by the end of World War II," explains Hong. "She pretty much walked away - apart from a TV series she did toward the end of her life.
"Once the Production Code was enforced there was nothing she could really play other than the villain or the temptress."
The Production Code - policy in Hollywood from 1930 to 1968 - frowned on suggestions of interracial sex and, combined with the tradition of using "yellowed-up" western actors to play Asian roles, meant Wong's options were curtailed.
The most crushing blow came in 1935, when Hollywood decided to turn Pearl S. Buck's Pulitzer Prizewinning "The Good Earth" into a motion picture.
Wong lobbied hard for the lead role of the pre-Chinese Revolution farmer's wife O-Lan but the fact that the MGM studio cast a major star for the male lead in Paul Muni meant - due to the Production Code - that Wong's hopes were dashed. She was, instead, offered the role of a concubine but turned it down.
In one touching scene in the documentary, an actress playing Wong read a letter she wrote asking why Asians are always portrayed as "crude" villains who were "murderous, treacherous."
"You are left with the feeling she never really recovered from that," says Hong.
"It was her dream to play that role and to really make a breakthrough in terms of an Asian actress as a serious lead. But it never happened and it's never really happened since either."
Hong's documentary draws on archival news and documentary footage, clips from Wong's films and on the actresses' own letters and interviews, in particular those sent to American writer and photographer Carl Van Vechten with whom she corresponded over 30 years.
Those letters reveal a woman who, though becoming despondent about her struggles, never really stopped trying.
"She really did give up everything for her career," says Hong. "Thoughts of marriage, her family - she put everything aside as she tried to make herself into a star.
"The problem was that the Hollywood studios were scared to cast an Asian woman as a lead, scared of the fact that the audience could not accept that.
"It remains pretty much the same today. The fact is that - in America at least - the Asian audience is small and studios won't take many risks."
The Seoul-raised Hong has been living in New York since 1985 and says the Wong project came about after she had made "Becoming an Actress in New York" (2000), which looked at the struggles of modern Asian-American actresses.
It took her eight years to source the material used and gather interviews with people who knew Wong and who knew her work.
Hong says she hopes that by re-telling Wong's story, she can inspire - as well as educate.
"Wong was such an important figure," says Hong. "Even if you look at Asian actress today - the likes of Lucy Liu - Wong achieved so much more at a time when it would have been infinitely harder for her as an Asian and as a woman.
"She was driven and she was brave and I think the lesson we can learn from her is how important it is to fight to find your own place in the world, no matter what the obstacles."