Twelve Jewish activists from Riga and Leningrad plotted in 1970 to hijack a Soviet aircraft and fly it to Sweden to call attention to the plight of Jews in the Soviet Union; people who were not wanted there but who were forbidden to leave. While researching his new book “When They Come for Us, We’ll Be Gone: The Epic Struggle to Save Soviet Jewry,” Gal Beckerman read everything he could find about the men, and he then interviewed them individually.

In 2005, Beckerman attended the activists’ 35th annual barbecue in Israel. “The banality of the barbecue was almost shocking,” recalls Beckerman, 34. “In my mind these men were like super heroes, and yet there they were, flipping burgers. It was a surreal experience, but helped me to see them as ordinary people. What made them extraordinary was that they could not accept the status quo.”

“When They Come for Us, We’ll Be Gone” (Houghton Mifflin Harcourt, $30) explores the nearly three-decade struggle for freedom of three million Jews living in the Soviet Union. The New Yorker calls the book a “wide-ranging and often moving history” that shows how ” after decades of mixed success, the movement played a critical role in the dissolution of the Soviet Union.”

Beckerman’s 598-page book combines meticulous research with a lively, conversational style that keeps a reader turning pages late into the night. Beckerman was first attracted to the tale of the refuseniks because of its complex nature.

“A lot of writers have a metabolism that requires them to jump from story to story, but I have the metabolism of a turtle,” says Beckerman, a reporter at the Jewish Daily Forward and former longtime editor and staff writer at the Columbia Journalism Review. He adds, “I love the notion of hunkering down and getting to the heart of a good story, learning all about it from different angles.”

Beckerman continues: “With this story, I had a giant canvas – a period of nearly 30 years, events taking place in three countries, and plenty of what I call ‘pinpricks’ of character, detail and narrative elements. It was incredibly challenging.” He interviewed more than 200 people, “sometimes for hours, sitting in their living rooms over cups of tea or – often – glasses of vodka and plates of pickled mushrooms.”

The project took Beckerman almost six years. He continued to work full time through much of it, and also found time to woo and win his wife, Deborah Kolben, who also is a journalist. They live with their year-old daughter, Mika, in Brooklyn. Beckerman was born in Los Angeles and spent much of his youth traveling between that city and Tel Aviv with his parents, Israeli immigrants.

In the book, Beckerman shows how the movement to win freedom for Soviet Jews established a strong identity among those who would leave Russia and mobilized the American Jewish community. Another revelation came to him incrementally. “As I went deeper into the research, I started to see the larger implications of the movement, and came to understood that what I was writing about was perhaps the most successful human rights campaign of the 20th century.”

Feedback on the book has been positive. “I am really heartened to hear how much people are enjoying reading the book,” says Beckerman. “I wanted to get the story right, but in addition to telling a comprehensive story, I wanted to tell an interesting story.”

What’s next for Beckerman?

He laughs. “Writing a shorter book.”