“Everybody professed to know her — they knew nothing about her,” an interviewee explains in a new trailer for “Billie,” an upcoming documentary that offers audiences the opportunity to “discover the legend,” the “mystery,” and “the real Billie Holiday.”

Introduced as “the world’s greatest jazz vocalist,” Holiday takes the stage and shows off her iconic pipes. But the spot also touches on who she was off-stage — the “beautiful soul that she could only express by singing.”

We also hear about how, in recording and singing “Strange Fruit,” a protest song about lynching, Holiday was “exposing discrimination” and putting it “on stage.”

Check out the trailer to see Holiday, who died at the age of 44, answering a question about “why so many jazz greats seem to die so early.”

“Billie” will hit theaters and premiere virtually November 13. The doc features interviews with Holiday’s family, friends, and the FBI agents who arrested her.