After becoming the fifth spirit, Elsa was unaware of the fact that she had become one of the immortal spirits. When the Man on the Moon chooses her to become the next Guardian, Jack Frost is sent to give her the news. Elsa, in disbelief, is brought along on a journey that she never even imagined possible when Pitch Black suddenly makes a reappearance after many years of being sealed away. And somewhere along the way, she finds that Jack Frost isn't so bad after all.