Arielle Kebbel in ‘Aquamarine’.Credit : 

Cinematic / Alamy Stock Photo

When it comes to 2000s movie villains, few are as iconic as Cecilia Banks.

Brought to life by Arielle Kebbel, the Aquamarine antagonist spends the entirety of the 2006 movie thwarting the titular mermaid’s efforts to find love with lifeguard Raymond (Jake McDorman), whom she wants for herself.

The bobbed high schooler has amazing style, an attitude problem and terrible driving skills — which she uses to secure lessons with Raymond in her vintage pink convertible complete with a “princess” vanity plate.

“She’s a princess?” Aquamarine (Sara Paxton) asks upon seeing the spoiled weatherman’s daughter’s ride, as her new friend Hailey (Joanna “JoJo” Levesque) quips back, “No, just a royal bitch.”

But Cecilia is so much more thanks to Kebbel, 41, who only agreed to play the somewhat prototypical mean girl if she could make some “slight emotional adjustments.”

Initially, however, Kebbel actually auditioned to play the titular siren in the 2006 fish-out-of-water tale — a role she tells PEOPLE she “really, really, really, really wanted” at the time. “I mean, my name is Arielle. Her name’s Aquamarine. We’re both mermaids. I was obsessed.”

Kebbel even showed up to her audition in a “horrific blue wig,” which was a nod to Aquamarine’s hair in the Alice Hoffman book the film is adapted from. It was a bold move, and it didn’t go over particularly well, the actress recalls, joking that she was probably the reason the hair and makeup team went for a subtler hairstyle. “Maybe they were like, ‘Yo, after that, we gotta cut it. It’s never going to work. It’s never going to work.’ ”

Elizabeth Allen Rosenbaum, who directed Aquamarine, still remembers Kebbel’s audition wig well. “I knew from the moment she walked in that I wanted to work with her,” the filmmaker tells PEOPLE. “She came in in a blue wig and she acted her heart out and she took real risks.”

“They asked me to come back for Cecilia,” Kebbel recalls, admitting, “I’ll be honest, it took me a minute because I was so heartbroken.”

“I really had to wrap my head around like, ‘Am I going to be OK emotionally going to set every day on a mermaid movie, not being the mermaid?’ That was a very real question,” the The Vampire Diaries alum remembers. “And then I was like, ‘Yes, of course I am. I want to be in this. What am I doing? Put my ego aside.’ ”

It was a decision that shaped Kebbel’s career for years to come. “That movie helped me find my voice on set maybe even more than they realized,” the actress tells PEOPLE, recalling that she was “very clear” about her take on Cecilia “going into it.”

“I needed her to be a mean girl with a heart or who cares, right?” she says.

Echoing this, Rosenbaum adds, “You want a villain who’s got a lot of layers and I feel like [Kebbel] showed [Cecilia’s] vulnerability and that was really nice. So you sort of understand where she’s coming from.”

“It was never scripted,” Kebbel recalls, “that I was almost crying when Daddy wanted to take away my car, but I thought that would add some humor and also kind of show a bit of vulnerability. It was never scripted that I screamed that way about, ‘She’s a fish!’ ”

“There was just these little moments that I really had so much fun playing with and asking to kind of do my own take on,” the John Tucker Must Die star continues, “and I think that helped give me confidence moving forward to speak up on other sets that I was new to and say, ‘Hey, can I try this? I kind of see it this way. Let’s see what that does.’ ”

Cecilia may not be the nicest, but she — like the main trio made up of Paxton, Levesque and Emma Roberts — is dealing with a lot. Namely, she is also struggling to wrap her mind around the existence of mermaids. She repeatedly tries to prove to her loved ones that Aquamarine is a siren, but nobody believes her.

“It’s absolutely a horror film from her perspective,” Kebbel tells PEOPLE of Cecilia’s lot in the 2006 film. “She’s going into cool girl summer, and she leaves a horror film.”

“She has lost everything,” Kebbel says of the character. “She’s lost the trust with her dad. She’s lost her car. She’s lost her popularity. She lost the boy. She can’t believe the fish is real. So I was coming out at a place from, like, ‘I have to make all of this very real to make these stakes high.’ And so I just thought, ‘Well, this is it. She’s losing it.’ ”

Cecilia’s role in the film is not as central as the main threesome’s friendship, but it is a crucial ingredient — and makes for a wildly entertaining ride. Two decades after the film’s release, it also remains “a very meaningful part of my life,” Kebbel tells PEOPLE.

On a recent flight, the Marshals actress recalls, a pilot “grabbed me and was like, ‘Can I take a picture? Aquamarine is everything.’ And I was just like, ‘Yeah, and you’re flying our plane.’ I was like, ‘What? Can I get a picture with you?’ ”

“So it definitely stands out as just being a continued special experience in my life,” she adds, “because when people come up to me and share their memories of the film, it just makes it that much more special for me.”