Sylva Zalmanson, a young newlywed, pantomimed a waltz in the solitary confinement of a Soviet dungeon. Her husband, Eduard Kuznetsov, sentenced to death, was somewhere, like her, as good as lost in the “gulag archipelago” of prisons. As she waltzed, she slowly moved her arms around no one, swaying, gliding through the tiny cell. While she danced, said Sylva later, “I remembered the life I once had when I was free.” Freezing in a Siberian winter, in thin clothes she jumped up and down, up and down, as if that mattered. Bugs crawled in the dark. In her soup was a dead mouse.

Sylva and Eduard’s crime was wanting to leave the Soviet Union and emigrate to Israel and, with 10 others, planning to hijack a small 12-seater aircraft, on June 15, 1970, for the 15-minute flight from Leningrad to the Finnish border. The KGB arrested them all before the plane took off. Eduard and Mark Dymshitz, the would-be pilot, were sentenced to death.

When the Soviet judge allowed her to speak, Sylva answered in Hebrew, “L’shana haba … Next year in Jerusalem,” adding, “If I forget thee, O Jerusalem, may my right hand wither.” The judge asked for an interpreter. Sylva said, “No need, I’ll translate it for you,” and she said it again in Russian.

Yosef Mendelevich, one of the conspirators, laughed at the memory.“ I saw the judge almost pass out; he realized the game was over. Whatever they [the Soviets] planned, would fail.”

Prior to the hijacking, Sylva had been working for Jewish rights and emigration in Riga. Eduard was not halachically Jewish but told Mendelevich that while he was in a prison camp, prior to meeting Sylva, that he “decided to tie his fate with Israel’s.”

The 12-seat plane Soviet Jews planned to hijack.

The 12-seat plane Soviet Jews planned to hijack.

The outrageous defiance of the would-be hijackers lit a flame under Soviet Jewry, both in Russia and among their supporters in the United States. Soviet Jews requesting permits to go to Israel, despite the grim reality that they would just as likely end up in Siberia, soared from 11,000 in the decade prior to the hijacking to more than 400,000 in the decade after. In New York, rallies were organized by everyone from Student Struggle for Soviet Jewry (SSSJ) to the Jewish Defense League to the Jews in suits, once mocked by the activists as “the establishment.” Glenn Richter, national coordinator of SSSJ, recalls that Azriel and Ahuva Genack, “our typical SSSJ grassroots,” organized a sold-out rally in Madison Square Garden “out of their kitchen on West 94th Street.”

Rabbi Meir Kahane told rallies, “If Jews die in Leningrad, New York is gonna burn! … If Dymshitz and Kuznetsov die, Russian diplomats will die in New York.”

All the would-be hijackers made it to Israel, at some point. Sylva was released in a spy-swap with the United States in 1974. Eduard, who, from age 22, spent seven years in the gulag before marrying Sylva, then spent nine of his first 10 years of marriage in the gulag again, before they reunited in Israel and had a baby, Anat Zalmanson-Kuznetsov. (They divorced a year later, each broken in their way, but without hostility). Now an Israeli filmmaker, Anat has completed a documentary on her parents’ journey, “Operation Wedding,” so-called because the hijackers’ original cover was that they were travelling together to a wedding. In the film, Anat returns with her parents, now both good humored and charming, to prison cells and their radical evolution.

The one-hour film, to be broadcast on Israeli TV, and scheduled for various film festivals, will have its New York premiere on Feb. 26 at Columbia University, where SSSJ held their first meeting in 1964.

Anat explains in the film, “Every since I was a little girl people always asked me, did you know that your parents are heroes? Growing up, everybody knew who my parents were. But in the last 15 years or so, their story has been forgotten.”

Richter tells us, the Jewish activists tried everything, “like pushing 15 buttons in an elevator, if only one would be right.” The film illuminates the behind-the-scenes story of the button that worked: Prime Minister Golda Meir asked Spain’s fascist leader, Gen. Francisco Franco, for help. He had just sentenced six Basque terrorists to death. “We know that you are descended from a Jewish family that converted during the Inquisition,” wrote the prime minister, “so we are pleading with you to help. You can save the lives of two innocent Jews by sparing the lives of six killers. If you do that, Brezhnev the Communist will try to prove that he is more humane than Franco the fascist.” Franco commuted the death sentences. Then Brezhnev did too.

Anat’s mother, who had been working for Jewish causes in Riga, told the camera that she tried several times to get out legally “but I was refused. They used to tell us, ‘You may rot here. But you’ll never get out. You’ll never see your Israel.”

Sylva was confident about the hijacking. She packed for Israel. Eduard feared the worst. He packed for prison.

The 12-seater didn’t give him any confidence. It was old, “very old,” he says now. But it was “enough to fly to the camp,” he laughed. “The concentration camp.”

“When I was 25,” says Anat, “my mother told me, when I was your age I was already in prison. I would like to go back in time and whisper to my parents that everything will be okay. I want to tell them the exact date when they would be released, the exact when they will be free.”

She asks her mother, “how did you say goodbye to your father?” Sylva pauses for a long while, bringing her hands over her face, as if in prayer. Her father was a widower. Now three of his children (including Sylva’s two brothers) would be gone forever, one way or another. “Instead of saying goodbye I just made his favorite food and cleaned the house. I didn’t leave him a note. It’s hard for me to even think about it.” The tears in her eyes said more.

With all the historical amnesia in the Jewish community, David Suissa, publisher of the Jewish Journal, and Knesset member Michael Oren, among others, have suggested a Jewish holiday to commemorate the escape of three million Soviet Jews, the greatest Jewish exodus since leaving Egypt. “The freeing of Soviet Jewry has become a vanishing story,” writes Suissa, “a hazy memory for some, a non-event for many, especially among the new generation… It’s [also] the story of American Jews who used the freedom they had in America to fight for the freedom of their brethren in a faraway land.”

Last June, Oren helped pass a Knesset bill creating Yom Ha’aliyah, for a celebration and study of aliyah, to be commemorated Nisan 10 (the day that the Israelites crossed the Jordan into the Land of Israel, the first mass aliyah). The first celebration of the holiday falls this year on April 6.

“Operation Wedding” will be shown Feb. 26, 3 p.m. at Columbia University’s Roone Arledge Auditorium (Lerner Hall), 2920 Broadway, sponsored by Aryeh, Columbia’s pro-Israel public affairs committee. Tickets are $10, and it is advised to book in advance at www.operation-wedding-documentary.com/nyc. Prior to the film, there will be a discussion of Soviet Jewry at 2:20 p.m. with author Gal Beckerman and David Harris of the AJC. At 4 p.m., there will be a Q&A with director Anat Zalmanson-Kuznetsov. At 7 p.m., one of the hijackers, Rabbi Yosef Mendelevich, will be speaking at Cong. Ohab Zedek, 118 W. 95th St. There is no charge for Mendelevich.