What is the rising action in the film Singin' in the Rain?

The rising action in the film Singin' in the Rain includes Don Lockwood's evolving relationship with Kathy Selden, the challenges faced by Don, Cosmo, and Lina during the making of "The Dueling Cavalier," and the unveiling of Lina's true voice during the premiere of the film. These events build tension and propel the story towards its climax.