Niklas-Frank in Hitler's Children.

Niklas Frank, son of Hans Frank, governor-general of occupied Poland.

THE Israeli filmmaker Chanoch Ze'evi says that his grandmother - a ''city girl'' with a taste for mink and manicures - emigrated from Warsaw to Palestine in 1933. In 1939 she planned to return for a visit, only changing her mind when she discovered she was pregnant.

''This is the reason I am talking to you now,'' Ze'evi says. None of his grandmother's family in Poland survived the war.

Some 60 years later, while researching a documentary for German TV, Ze'evi found himself drinking coffee in the apartment of Traudl Junge, Hitler's secretary.

''She didn't even hide from me that she was still admiring Hitler,'' he says. ''I remember that she went to another room to bring a picture of her with Hitler - it was after I'd showed her a picture of my daughters.''

Until then, Ze'evi had focused on making films about the Holocaust from what he calls ''the classic point of view'' - the point of view of the survivors and victims. Talking to Junge, he says, made him realise there was another side to the story.

''I think it's important to get a dialogue between the two sides, the victims and the perpetrators.''

The result is his new documentary Hitler's Children, which focuses on interviews with present-day descendants of high-ranking Nazis. Each has found a different way of coping with a horrific legacy.

Niklas Frank - the son of Hans Frank, the governor-general of occupied Poland - now tours German schools telling scarifying anecdotes of his childhood. (He remembers being taken to see a concentration camp and roaring with laughter at skinny inmates falling off a donkey.)

Katrin Himmler, the grandniece of Heinrich Himmler, dismisses the idea she could have inherited any of her great-uncle's traits: to believe otherwise would be to echo the ''ridiculous ideology'' of the Nazis themselves. By contrast, Bettina Goering, grandniece of Hermann Goering, has chosen to have herself sterilised: ''I cut the line.''

Making the film, Ze'evi says, was a long, difficult process. Initial research took more than a year. Then there was the challenge of finding people to be interviewed. ''Some of them just slammed down the phone, others asked us not ever to try to call them again.''

It was crucial to explain to potential participants that he did not plan to exploit or attack them. ''Because it's very easy to do such a film … with horrible pictures from the Holocaust and then speak to the grandchild, or the grandniece, of these murderers, and immediately, in this cut, you blame them, even though they are only the descendants.''

Ze'evi says the people who appeared in the film are those who are driven, one way or another, to talk about their families' shame. ''They cannot keep it inside.'' What surprised him most was the realisation that his subjects were exceptional. ''In those families many members are still loving the father, or they're still holding the Nazi ideology.''

Is it ever possible to escape the past? Ultimately, the film leaves this question open. ''I don't have the right to say case closed and there's an end to this story,'' Ze'evi says, ''because I am not a Holocaust survivor myself.''

But, he says, ''more than 70 years later we can discuss themes regarding the Holocaust that we couldn't do even 15 years ago.'' In some sense, ''the time has come to move on.''

Shortly before shooting, he went alone to the camps in Poland in order to ''reach out'' to the past. ''I remember the exact place where I was walking in Auschwitz in block 10 - and suddenly I felt that I don't have the strength to do this project.''

On returning to Israel, he decided again that the film was necessary. ''But it's just an example - to understand how sensitive it was for me.''

Hitler's Children is screening as part of the Jewish International Film Festival.