The Movie Every Kissing Booth Fan Needs To Watch Before It Leaves In December

McAdams wound up being the last actress to audition for the role of Allie, but her approach also turned out to be the best. The actress was unknown to both Cassavetes and Gosling at the time, but she blew them away with her performance, and even she knew it was a successful tryout right away. "I read the script the night before and bawled my eyes out. I'm surprised that I even got up the next day. I was just wrecked by it," McAdams explained in a behind-the-scenes feature for the film. 

Gosling was particularly impressed by how unshakable she was in her delivery of the lines. "Every girl wanted to talk about the scene and the character and all of these things, and we talked about it just endlessly," he remembered. "But Rachel came in, and we were like, 'Do you want to talk about it?' She was like, 'No.'"

McAdams described her final scene read as "electric," adding, "It was just a feeling there. Everything fit. Everything worked. It was the best audition experience I've ever had. And I just walked out of that room, and I was just in another world. I just couldn't catch my breath." Gosling later told ScreenSlam that what sold him on McAdams for the role was her confidence, saying, "She came in, and she just took the role. And it was clear to me anyways that this was an actress that I wanted to work with. In the audition I just felt like she not only was talented, but she had a lot of opinions, and she was going to fight for those opinions. She wasn't going to be swayed or manipulated."