“Singin’ in the Rain” casts Debbie Reynolds as Kathy Selden. A humble chorus girl with dreams of superstardom, Kathy gets her shot at the big-time upon meeting Don Lockwood (Gene Kelly), an in-demand silent film star struggling to stay afloat as “talkies” become the hottest new thing in late-1920s Hollywood. It’s the perfect example of art imitating life. Reynolds, like Kathy, was determined to earn her stripes with “Singin’,” even if that meant having to keep pace with Kelly and Donald O’Connor. At the time, those two were already masters of their craft at the height of their popularity, with (collectively) decades of experience singing and dancing on the big screen under their belts.

Whereas Reynolds, on the other hand, basically had none.

“You know, I was so dumb that I didn’t feel you could fail. I felt [the role] was me, and I marched straight ahead,” a smiling Reynolds told the American Film Institute in 2012 (via Vox). She added:

“To dance with Gene Kelly and Donald O’Connor in three months — well, anyone else should’ve passed out. But I didn’t. I just thought, ‘Well, let’s get started.'”

Reynolds readily proved she was more than right to have such unbridled confidence in herself. With only those three months of preparation, she managed to go toe to toe with Kelly and O’Connor, most notably during perhaps the film’s most enchanting musical number, “Good Morning.” Capping off a night spent racking their brains about how to salvage Don’s disastrous post-converted talkie “The Dueling Cavalier” (turn it into a musical, of course!), the scene sees Kathy, Don, and Don’s BFF Cosmo Brown (O’Connor) cheerfully tap-dance a storm across Don’s house in celebration, grinning and crooning a harmonious melody as they do. It’s an instance of genuine movie magic.