Richard Trank first became aware of Simon Wiesenthal when he was 12 or 13 years old. “It must have been around the time of my bar mitzvah,” Trank said in a telephone interview.

“Someone gave me a copy of his book, ‘The Murderers Among Us,'” he continued. “My father lost most of his family in the Shoah. When I read the book, I was just blown away to see that my grandmother and uncle didn’t die in vain.”

So in a sense it was beshert that years later Trank, 52, went to work for the Wiesenthal Center in Los Angeles. It is even more fitting is that he both co-wrote and directed the biographical documentary, “I Have Never Forgotten You: The Life and Legacy of Simon Wiesenthal.” The film opens Friday, June 29 at the Roxie New College Film Center in San Francisco.

Trank is the principal writer and director for Moriah Films, which is part of the Wiesenthal Center. “We have for many years kicked around the idea of doing a film about [Wiesenthal]. But we shied away from it, because we thought it would be perceived as too self-serving,” Trank said.

That changed in the fall of 2005, when Trank was in a Los Angeles editing room finishing his previous documentary, “Ever Again,” about the resurgence of anti-Semitism in Europe.

“It was about 11 at night when a young man, a 20- or 21-year-old kid who works there, came in and told me he just heard my boss had died.”

Trank automatically assumed the man referred to Rabbi Marvin Hier, dean and founder of the Center. But the worker meant Simon Wiesenthal, who, except for his name, has no direct connection with the Los Angeles center.

Then the young Latino “proceeded to tell me how he had gone to the museum a couple of times as a student, and how he admired [Wiesenthal]. He’d become a hero to this young kid from the east side of L.A. who logically would never have any connection with a 95-year-old Nazi hunter. That’s when I realized we really need to [make this film].”

Coincidentally, Trank was in the process of preparing an exhibit about Wiesenthal and his work for the organization’s Museum of Tolerance, so he’d already gathered archival material.

Though Wiesenthal had done dozens, perhaps even hundreds, of television interviews, very few were in-depth. He had, however, sat for three days and spoke in German for the cameras of the Shoah Foundation. There were some additional resources, including an interview that covered the early years of his life until the war years that had been done a more than a decade ago. But he had grown tired that day, and the idea was to resume the interview later. It didn’t happen.

Still, there was enough basic material around to tell the Wiesenthal story: Born in what is now Ukraine, Wiesenthal was trained as an architect. He lost close to 90 relatives in the war, and barely survived himself. Almost immediately after the war, he volunteered to help the Allies root out war criminals, until they lost interest. Then he decided to pursue them on his own. Most famously, he was responsible for finding Adolf Eichmann and more than 1,000 others.

To fill out the story, Trank and his crew traveled around the world, revisiting camps where Wiesenthal had been held, cities where he’d grown up and even homes of some of the Nazis he’d help capture. Most of the visits were without incident.

Once, though, in Austria, “we were looking for the home of one of the people Simon had been after, and we definitely got the feeling we were not welcome.

“It was in Linz, fairly close to Mathausen [the last camp Wiesenthal was in],” he continued. “It was a picturesque farming area, and we wanted to drive up the road to where the farm [of the war criminal] was. The road was blocked by a guy in lederhosen. It turned out to be the son of the Nazi. He made it clear that we shouldn’t make him any angrier than he already was.”

Trank and company left. “You have to know when you’ve overstayed your welcome.”

But bringing the film to life had more good moments than bad. Shortly after he began assembling the documentary, Trank brought an eight-minute version to a fundraiser in New York. As luck would have it, Nicole Kidman was there, sitting next to Rabbi Hier. When she saw the extended trailer and heard about some of the others who had narrated Moriah films — Kevin Costner, Morgan Freeman — she immediately volunteered her services.

Recently, after a private screening in Jerusalem, two women asked Trank to settle an argument: Is Nicole Kidman Jewish? The question came up because they thought Kidman was a Jewish name and because her pronunciation was pitch-Jewish-perfect. (For the record, she isn’t.)

Another happy moment occurred during the film’s international premiere at the Berlin Film Festival. “The German distributor put huge posters all over Berlin, so when you entered Alexanderplatz, where a lot of the main action was going on, all you saw were these posters of Simon looking down at you.

“It was very emotional to see the response,” he continued. “All the screenings were sold out. There were old people, young people.”

To his credit, Trank produced a balanced picture of Wiesenthal. “I think the film is very honest,” he said. “When I started work on this film, I felt it very important that it be an honest film. So we talked about all the good things he did, but we also talked about his foibles.

“I don’t think it would get into the festivals it’s been getting into, and getting the reaction it’s getting, if it weren’t an honest film.”

“I Have Never Forgotten You: The Life and Legacy of Simon Wiesenthal” opens at the Roxie New College Film Center Theater, 3117 16th St. S.F., on Friday, June 29.