David Rapaport’s kindergarten teacher knew the casting director’s calling before he did.

It was June of 1984, and it was time for Rapaport’s year-end report. On it, his teacher wrote, “He assigns ‘parts’ to others.” Thirty-five years later, the Boston native has made a career out of assigning parts to others. He’s best known for his casting prowess on a number of Warner Bros. series, from Gossip Girl to Riverdale, and for working with producer Greg Berlanti on The CW’s Arrowverse shows. As a kid, “I loved going to movies and watching TV and getting excited about specific actors and specific performances,” says Rapaport, 40. During his final semester at Emerson College, he flew out to Los Angeles for two internships: one with casting legend Mali Finn—who worked on Titanic, The Matrix, and L.A. Confidential, to name a few—and one as a production assistant on Fox’s Party of Five. But when Party of Five was canceled on his first day, Rapaport put all his focus on casting. “I was crushed. My [Party of Five] internship ended and I had to spend all my time and credits at Mali Finn, which was the best thing that ever happened,” he says. “It was a bit of a happy accident.” The three-month internship led to a five-year job, emboldening Rapaport to try his hand at becoming a casting director. He thought he’d made it big when he got a general meeting with Warner Bros. “I left that room thinking it was the best meeting I’d ever had, and I was waiting for their phone call,” Rapaport says. “They didn’t call for two years.”

When they did call, it was for a little 2007 pilot called Gossip Girl, which came from The O.C. executive producers Josh Schwartz and Stephanie Savage and followed the drama-filled lives of New York City’s Upper East Side residents. “They said, ‘We need the next Mischa Barton and the next Adam Brody,'” Rapaport recalls. “With my youthful cockiness, I said, ‘Of course!'” Finding those perfect actors was about as simple as hosting a Blair Waldorf-approved soiree. But eventually Rapaport delivered Blake Lively and Penn Badgley, and that success led to him casting The CW’s 90210 reboot the following year. Eleven years later, his company, Rapaport/Baldasare Casting—where he works with his business partner, Lyndsey Baldasare—currently oversees the casting for five shows on The CW, two on Netflix, and one on DC Universe.

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In his L.A. office on a Thursday in March, Rapaport is hard at work poring over actor submissions for the roles they’re currently trying to fill. The part he has pulled up on his computer screen has more than 800 submissions. It’s a guest-star role for which Rapaport says they’ll bring in 20 to 25 actors. If this were a pilot? They’d get even more submissions, and with the help of casting directors in places like New York, London, and Australia, they’d bring in hundreds of actors. Oh, and they’d do it all in a limited amount of time. They generally have 3 to 8 days to cast an episode and 8 to 10 weeks to cast a pilot. According to Rapaport, they use that time to look through every single submission and self-tape. “You only have to see one person to play the role, so if I miss that one tape, I’m devastated,” he says, comparing what he does to matchmaking. In a way, he spends his days looking at professional Tinder pages, trying to find the right person for any given project. (So in more ways than one, he has mastered the “chemistry read.”) And, together with the casting departments at both The CW and Warner Bros., Rapaport works to turn a giant dating pool into a handful of appealing prospects—until ultimately the producers, studio, and network decide which actor is “the one.”

Over the years, Rapaport has created a network of actors that he draws from time and time again. “If you’re in the business long enough, it does start to feel like a small pool,” Rapaport says. “You start to get your favorite actors that you keep bringing in.” For example, if they’re bringing in 20 actors to read for a part, Rapaport estimates that 10 to 12 of them will be people they know. But he’s always open to new faces, which is precisely why he’s going to click through all 800 submissions currently waiting for him on his computer.

While he sifts through the deluge of headshots to find TV’s next big star, we look back at some of his biggest casting coups.

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Blake Lively, Gossip Girl There could only be one Serena van der Woodsen, and Rapaport knew he had to get the casting right. “They were looking for someone who was casually cool, effortlessly chic, and—as a performer—was able to access their feelings,” Rapaport says. “I was looking for this perfect person that would deliver on every level.” And to fill that tall order, he had just one individual in mind: Blake Lively, whom he’d seen in 2005’s The Sisterhood of the Traveling Pants. “I did not have another choice,” Rapaport says. “I knew in my heart there was no one else.”

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Stephen Amell, Arrow Rapaport’s long relationship with casting CW superheroes began with Arrow and the search for the right man to wear Oliver Queen’s green hood. “They said to me, ‘We want someone that looks like a superhero and can act,'” Rapaport remembers. “I had just cast Stephen [Amell] in a guest spot on 90210, and it was a pretty dramatic role. He had the muscles and that kind of dark mysterious look behind his eyes, so he was the first person I thought of when I read the Arrow script.” Amell was also the first person to read for the part.

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Grant Gustin, The Flash When it came time to cast the next Flash, the direction was almost the opposite of Oliver Queen. The Flash shouldn’t look like a superhero, Rapaport was told. “We were looking for someone who was relatable, someone that was an Everyman who was bestowed with superpowers—someone a little bit goofy,” he says. Like Amell, Rapaport had cast Grant Gustin on 90210. He’d also seen him play bad-boy Sebastian on Glee. “But every time I met Grant, he seemed like this affable, dorky, charming, fun dude,” Rapaport says. “He was the first person I auditioned for the role. We read him opposite [Arrow’s] Emily Bett Rickards, and there was amazing chemistry there.”

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Melissa Benoist, Supergirl Occasionally producers will give Rapaport a prototype for what they’re thinking about for a character, someone who is a star version of what they’re hoping to find. For Supergirl, the prototype was Jennifer Lawrence. Rapaport took that and ran with it. “There’s a quality about Jennifer Lawrence, an openness, a goofiness. She’s relatable,” Rapaport says. In trying to find those qualities in someone else, he remembered Melissa Benoist, who had read for both Arrow and an MTV pilot Rapaport had worked on. “I got to know Melissa, and she seemed to encapsulate all these qualities they were looking for,” he says.

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KJ Apa, Camila Mendes, Cole Sprouse, and Lili Reinhart, Riverdale Finding Archie, Veronica, Jughead, and Betty meant sifting through a mixture of new, familiar, and semifamiliar faces for Rapaport. Lili Reinhart, who eventually landed the role of Betty, had previously read for Arrow. “I’ve been reading her since she was 14 years old,” Rapaport says. “This was a reinvention of the comics, so we knew it was going to be a bit of a darker tone, and from what I’d known from Lili, she was a person with a lot going on underneath.” Rapaport read Reinhart at the same time as Cole Sprouse. “Initially I was bringing in all these lanky, charactery-type guys for Jughead, and Cole brought such a dark, brooding, intense essence to the character. [Cole and Lili] defined, for me, what the tone of the show might be, which was teen noir.” Camila Mendes and KJ Apa—who play Veronica and Archie, respectively—were both brand-new to Rapaport. He cast Mendes out of college, while Apa nearly missed his big break. “I passed on him the first time he came in,” Rapaport says. “He didn’t seem prepared.” But when they couldn’t find the right guy for Archie, the actor got a second chance. “He came back in and his read blew me away,” Rapaport remembers. “Sometimes people have bad days and you miss something.”

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Nicole Maines, Supergirl As an openly gay man, Rapaport says one of the biggest and most fulfilling challenges of his career has been casting LGBTQ actors in LGBTQ roles. “One of the reasons I wanted to work with Greg Berlanti, an openly gay producer, was to work on projects that highlighted LGBTQ characters and story lines,” Rapaport explains. And when Supergirl added the character of Nia Nal, also known as Dreamer, he had the chance to cast a transgender superhero. “I was scared because I wanted to get it right,” says Rapaport, who cast a wide net before landing on Nicole Maines for the role. “She’s from Maine, so she took a little bit of digging to find. But this was such a great opportunity to tell an amazing story, and Nicole is a great actress and an outspoken activist. She’s such a hero to me.”

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