If Catcher in the Rye author J.D. Salinger were alive today, he probably wouldn’t be happy with the attention a new movie and book about his life are getting. The famously reclusive author is the subject of Salinger, a documentary (out Sept. 6) that will be released jointly with a biography (out Sept. 3) of the same name. Salinger guarded his public image obsessively after he became famous, but director and screenwriter Shane Salerno managed to find brand new facts and photos after years of research and hundreds of interviews. The Weinstein Company has been keeping the bombshells Salerno uncovered under wraps, but EW has obtained a never-before-seen photo of Salinger from the project. Salerno explains how he found this photo and what it means.

ENTERTAINMENT WEEKLY: How did you find this photo? Who owned it?

SHANE SALERNO: This is a special picture, taken by Paul Fitzgerald, who served alongside him as a counterintelligence agent in World War II and maintained a close friendship with him from 1944 until Salinger’s death in 2010. This is one of many exclusive, intimate, never-before-seen photos of Salinger that appear in the film Salinger, which I directed and produced, and in the book of the film, which I co-wrote with David Shields. Among many other revelations, the film and book show the public the first ever images of Salinger at war. I always knew such photos existed, but it took me nine years to locate someone who not only had the photographs but was willing to allow me to use them in my film and book.

Why have we never seen it?

No other book about Salinger has a photograph of him during the war. Salinger was such a deeply private man that it took years to secure the participation of the people involved. They all found it hard to share intimate photos, diaries, and letters, but once they realized how committed we were to telling the full story, people trusted us with their stories, memories, photographs, documents, and other materials related to Salinger.

Where was the photo taken? And when?

During the Liberation of Paris, late August 1944, was an ecstatic day for Salinger and the other members of the Allied forces. It’s extremely unusual to find a photo of Salinger smiling like this—the flip side of the dark, sullen soul that is perpetually portrayed.

Why is this a pivotal moment in Salinger’s life?

It places him at the liberation of Paris, and World War II would be the crucible of his life. He entered the war as a Park Avenue rich kid and returned home in 1946 a shell-shocked soldier suffering from Post-traumatic Stress Disorder. Also, the photo was taken immediately before he met his idol, Ernest Hemingway, in a Paris hotel room, where Salinger gave Hemingway a copy of the Saturday Evening Post in which Salinger’s story “Last Day of the Last Furlough” had appeared. Hemingway expressed his admiration for Salinger as a soldier and writer. This photo captures Salinger during and just before two of the seminal moments of his life.

Do you think this moment factored into his later work? And how?

There were two emphatic demarcation points in Salinger’s life and World War II was the first. The war destroyed Salinger the man but created a great artist. All of the work that we know and celebrate Salinger for was written after the war. In the horrors of war Salinger found his voice, his post-traumatic tone. He never before had really written full out about either love or squalor. From 1946 untill he stopped publishing in 1965 he would write about nothing else.