Philadelphia (CW Philly) — When you’re invested in a show, it’s hard to imagine another actor portraying your favorite character. Take Gossip Girl’s Serena van der Woodsen for example. Could you picture someone other than Blake Lively portraying Upper East Side’s “it girl”? Well, according to casting director David Rapaport, the iconic role could have went to Ashley Olsen. 

Pictured (L-R): Ashley Olsen // Blake Lively
Photo Credit: Getty Images/ Matt Winkelmeyer/MG18 / Contributor/ Stephane Cardinale – Corbis / Contributor

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“I think the network initially pitched us Ashley Olsen and Rumer Willis for Blair and Serena,” Rapaport told Buzzfeed back in 2015. But, “Blake Lively was literally the only person I could think of for Serena,” he said.

While picking Lively was an obvious choice for Rapaport, casting Serena’s beau, Dan Humphrey, wasn’t so clear-cut.

“Before Penn was involved, I desperately wanted Alden Ehrenreich to play Dan,” Rapaport told Entertainment Weekly. 

Pictured (L-R): Alden Ehrenreich // Penn Badgley Photo Credit: Getty Images/ Jun Sato/ Contributor/ JB Lacroix/ Contributor

Rapaport’s résumé doesn’t end with Gossip Girl. He was also involved with casting your favorite CW superheroes, like the Green Arrow.

“They said to me, ‘We want someone that looks like a superhero and can act,’” Rapaport reminisced. “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.”

Rapaport also cast Grant Gustin to be the leading red speedster in The Flash. 

“We were looking for someone who was relatable, someone that was an every man who was bestowed with superpowers—someone a little bit goofy,” he explained. “Every time I met Grant, he seemed like this affable, dorky, charming, fun dude.”

And with Gustin landing the title role, his love interest, Iris West, had to be cast. But Candice Patton wasn’t the only actress in the running.

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“We had seen Candice initially, but I think we were too early on in the process to cast her so we ended up testing Keke Palmer and this other girl, but they felt a little too young next to Grant [Gustin],” Rapaport told Buzzfeed. So, they eventually brought Patton back, and according to Rapaport, “it was magic.”

Pictured (L-R): Keke Palmer // Candice Patton Photo Credit: Getty Images/ Robin L Marshall/ Contributor/ Randy Shropshire

Rapaport was also tasked with finding the leading lady in The CW’s Supergirl. To help with this process, producers gave him a prototype: Jennifer Lawrence.

“There’s a quality about Jennifer Lawrence, an openness, a goofiness. She’s relatable… I got to know Melissa [Benoist], and she seemed to encapsulate all these qualities they were looking for,” Rapaport said. And voilà, Supergirl was found.

Rapaport’s works spans past the Arrowverse. The casting director also worked to find the right actors and actresses to take on Riverdale. 

When casting the show’s protagonist, Archie Andrews, Rapaport didn’t immediately go with KJ Apa. It was when the 21-year-old actor returned for another audition that Rapaport was convinced.

“He [KJ Apa] came back in and his read blew me away. Sometimes people have bad days and you miss something,” he said.

But, according to Camila Mendes, who plays Veronica Lodge on the show, Betty Cooper could have been portrayed by Katherine Langford instead of Lili Reinhart.

“I remember we [Mendes and Langford] went out and we got falafel with a guy who was auditioning for Archie,” Mendes told Entertainment Weekly.

Pictured (L-R): Katherine Langford // Lili Reinhart  Photo Credit: Getty Images/ Monica Schipper/ Stringer, Jerritt Clark/ Stringer

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So, there you have it, some fun CW casting secrets. We want to hear from you- what do you think of the stars who were almost cast versus those who landed the roles? Sound off in the comments!