Film maker Brooke Goldstein traveled to the West Bank and filmed more than five hours of interviews with terrorists and their brainwashed children. She went into it believing the situation had been exaggerated—but found it was worse than she could have imagined: Recruited To Die.

As the group walked through the town, they spoke to Palestinian Arab children in schools and on the street. “Our fixer was encouraging us to speak with the children. I think I’d always, deep down, had a hard time thinking the problem was really that bad. I thought maybe it was a lunatic fringe,” she said.

In fact, the fanaticism was worse than she ever imagined. “The most shocking thing was reconciling the normal appearance of these kids and what was coming out of their mouths,” she said. “I was holding these beautiful children in my lap, and my translator was translating words of hate.”

The story was always the same. “No child ever said, ‘I don’t want to be a martyr.’ They talked about fame, paradise, virgins, and Ferris wheels [after death]. They were happy to tell me they hated Jews,” she said.

The children were more fanatical than their parents. “When we interviewed Hussam’s family for the film, his parents were distraught. They don’t believe in this whole child suicide bomber concept,” Ms. Goldstein said. “Then I interviewed his sister, who was like, ‘I’m so proud of my brother. Hamas says he’s a hero.’ At one point she had a loser, dwarf, mentally handicapped brother. Now she’s the coolest girl in class, and very proud.”

In addition to the children, Ms. Goldstein interviewed Mr. Zubeidah, commander of the Al-Aqsa Martyrs Brigades in Jenin. At the time, the Israel Defense Forces had made five attempts to assassinate him. In person, Mr. Zubeidah was not the harsh figure she had expected. “It was like talking to any other kid, about 27 years old,” she said. “He was smiling. My translator told me, ‘He’s talking about killing Jews.’”

“The Making of a Martyr” is being shown at the Brooklyn International Film Festival on Saturday and Tuesday.