Literary legends Robert Caro and Robert Gottlieb are set to be in a documentary that highlights their race to complete their final book

• "Turn Every Page" director Lizzie Gottlieb spoke to Insider about her documentary.
• It centers on her father, editor Robert Gottlieb, and author Robert Caro, who penned "The Power Broker."
• The film follows as Caro completes his much-anticipated fifth and final volume of his Lyndon Johnson biography.

The work of Pulitzer Prize-winning author Robert Caro and famed editor Robert Gottlieb is the stuff of legend in the world of literature. And now the story of their famous collaboration is being made into a documentary.

For the last five years, filmmaker Lizzie Gottlieb, the daughter of Robert, has been working on "Turn Every Page," a doc that chronicles the work the two have done together over the last 50 years, including the iconic Robert Moses biography, "The Power Broker," and the heralded four-volume biography, "The Years of Lyndon Johnson."

The movie also delves into the relationship between the two as Robert, 89, patiently awaits Caro, 85, finally finishing his much-anticipated fifth LBJ volume.

"They are not slowing down because of their age," Lizzie told Insider in her first interview about the project. "I think they both feel the enormous weight to finish [the final LBJ] book."

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"I very much wanted this to be a story about them finishing their life's work, not just a retrospective of their lives and how impressive they are," she added.

Caro's biography, "The Power Broker," centered on the urban planner, received the Pulitzer Prize in 1974 and was chosen by the Modern Library as one of the hundred greatest nonfiction books of the 20th century. His four-volume biography of former president Johnson is regarded as the most revealing examination ever of an American president.

Throughout his career, Robert has been the editor-in-chief of Simon & Schuster, Alfred A. Knopf, and The New Yorker. Over the last 65 years, he's published and edited writers such as Joseph Heller, Michael Crichton, John le Carré , and Roald Dahl.

Insider has exclusively viewed a sizzle reel of the documentary, which is currently in post production. Along with featuring interviews from the likes of former president Bill Clinton, Ethan Hawke, Conan O'Brien, and The New Yorker editor David Remnick, it also shows the movie's "race against time" vibe, as Gottlieb describes it, with its look inside the methodical process Caro is going through to finish his final LBJ book and Gottlieb's stoic patience to finally one day edit it, despite the two being in the autumn years of their lives.

Lizzie said initially both her father and Caro declined being featured in a documentary. But after a lot of convincing, and seeing who the filmmaker was reaching out to for the doc, Caro was on board.

Since then Lizzie has been following both men, at first only separately, never on camera together.

"Caro didn't want to be filmed in the same room as my father because he said it might get contentious," Lizzie recalled, noting that in their time working together, Caro and her father have argued over almost every editing decision, even the placement of punctuation.

"That has over time changed," Lizzie said the film shows.

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Most of the filming was completed before the COVID-19 pandemic. However, the interview featuring Clinton was done just recently. But Lizzie said that was easily pulled off because the former president has a camera studio inside his home. So she simply had to do it over Zoom.

"They told us, 'This is what we did when Bill had to talk at the Democratic National Convention. Would this be good enough for you?'" Lizzie recalled with a laugh. "It definitely was."

Nearing a rough cut of the movie, Lizzie said there are still a few more aspects of their lives she wants to capture, including 140 boxes of Caro's papers, which feature original manuscripts of his books with Robert's edits in it, which are being acquired by the New York Historical Society. She would also like to interview former president Barack Obama and former Georgia House Minority Leader Stacey Abrams, who have both spoken in the past about how Caro's work has inspired them.

The movie, produced by Lizzie, Joanne Nerenberg, and Jen Small, has a fiscal sponsor through New York City arthouse staple, Film Forum, and is seeking finishing funds.

"We have been very lucky to have enough financial support to get to this point and we are on the brink of trying to pitch the movie," Gottlieb said, noting that she doesn't know when the film will be completed. "We are discovering the story as we go and are really trying to honor these two extraordinary men, who are doing something that I think really matters."

Learn more about "Turn Every Page."