In 1970, an obscure magazine printed by the U.S. government for distribution in the Soviet Union, called Amerika, commissioned New York City-based photographer David Attie to shoot behind-the-scenes at a hot new television show still in its first season: Sesame Street. The publication only ran a few of the photos, and the rest of the slides and negatives were tossed in a box and stored in Attie's brownstone closet in Gramercy. Decades later, his son — TV writer-producer Eli Attie — unearthed them.

There were nearly 500 photos in the treasure trove Eli discovered, and now around 150 of them are part of a new book called The Unseen Photos of Street Gang: How We Got To Sesame Street, a companion piece to the documentary Street Gang: How We Got To Sesame Street (coming to HBO on December 13th). The book was written by Trevor Crafts, the producer of the documentary, with a preface from Eli, who provided the photos for the joint projects.

Below, Eli discusses how the previously unseen Sesame shoot was originally commissioned for Cold War propaganda, and is just one sliver of his father's work, which he says he's not nearly done sifting through and cataloging yet.

When did you find the photos? I first found my dad's Sesame Street negatives about five or six years ago now. It was all very random, actually. One day, I was procrastinating from some script I was trying not to write, and something made me google my father's name. Almost nothing turned up. Which bothered me a lot, frankly, more than I expected. Here was a guy who'd had a fine career, and done some really compelling work, in my biased opinion -- not to mention, he was my dad and I loved him -- but because he died before the creation of the Internet, he really had no digital footprint at all. All but forgotten-dot-com.

That's when I decided to try to send around some of his photos, and see if I could somehow interest a gallerist or a curator or somebody in the art world. And nobody cared. That's putting it mildly. I couldn't even get people on the phone to give me general advice. It turns out that the art world is a pretty merciless place. As I say in the book, at least in Hollywood, people will ignore you over coffee.

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Meanwhile, a close friend of mine was pals with a prominent rock photographer, Kate Simon, who did agree to give me some advice over the phone. She told me: famous people. Gather any pictures your father took of famous people. That's the only way anybody's gonna care. That's when I started digging through the archive, very specifically looking for celebrity juice. And that's when I found this great trove of Sesame photos (in addition to photos of Truman Capote, W.E.B. Du Bois, Carl Reiner, Ralph Ellison, and on and on and on). None of which I'd ever seen, not even once. Which is amazing to me now. My dad just did the assignment, moved on, and stuffed the negatives in an overcrowded closet in the house where he lived and worked (and where my mom, the feminist painter Dotty Attie, still lives and works today). The exact same place I found them decades later.

David Attie holding Bert and Ernie.

What had your dad told you about his time documenting Sesame Street, if anything? My dad died when I was still a kid, so he didn't tell me much about it -- not that I can recall, anyway. But my brother and I lived and breathed Sesame Street when we were little kids. My brother Oliver was actually on the set for this shoot, so he's throughout this new book, and even made an appearance in an episode back then, sitting in Mr. Hooper's Store. So just the fact that our dad had done this was amazing to us. At that age, the fact that he had photographed Leonard Bernstein and Truman Capote and Lorraine Hansberry would have meant nothing to us. But Big Bird? That was like an audience with the Pope. I can't quite believe I didn't ask him more about it at some point. My brother, on the other hand, remembers it very well -- including the fact that, in Mr. Hooper's Store, he was given a "soft drink," but it was really just an empty, dusty glass. Show business has some hard truths -- something I didn't learn for another 30 years.

How did this shoot come about, to the best of your knowledge? Maybe the single most amazing thing about these photographs is that they were actually taken as Cold War propaganda. No joke.

A photo that ran in Amerika.

My dad did a lot of work for a magazine called Amerika (also known as America Illustrated), a big, glossy publication that featured a lot of top authors and photographers, and was printed by the U.S. Information Agency (later folded into the State Department, in the '90s). It was made for distribution solely in the Soviet Union. To teach them the joys of capitalism and democracy, in fact -- part of our massive Cold War propaganda effort, the largest in the history of the world at that time. But a number of American diplomats have told me that, actually, Amerika was barely distributed at all; Soviet officials claimed that no one there wanted a glossy magazine about our heathen country, and returned most of the copies as "unsold." Even as they fetched enormous prices on the black market. So really, these images (just two of which made the original spread) were barely seen at the time, and then never seen for decades afterward.

I don't know how my dad was given this particular assignment, other than the fact that he did a lot of work for Amerika in general. And he was good friends with the art director, a lovely man named Lee Battaglia, who's still around. For instance, my dad did a big cover shoot of Bobby Fischer for Amerika, six months before Fischer won the World Chess Championship. Amazingly, he got that gig because Fischer rejected the first guy they hired, Richard Avedon (who had the same mentor and teacher as my dad, Alexey Brodovitch). Fischer thought it would be demeaning to be photographed by a "fashion photographer." Which, of course, is a minuscule fraction of what Avedon was. This is especially ironic because, if Avedon had photographed Fischer, they would absolutely be the best-known images of the chessmaster, and probably ubiquitous today. My dad's -- which are incredible -- sat in a closet for decades, unseen by anyone. Just like the Sesame shoot.