Princess Tutu

Plot
Long before the story's timeline, a writer named Drosselmeyer from Gold Crown (Kinkan) Town, played with others' fates using stories that became reality. For this behavior, his hands were cut off and he was killed by those fearing his power. Drosselmeyer's final story was thus left unfinished, and the Prince and The Raven in it were locked in eternal battle. After many years had passed, The Raven broke free from the story and into the real world, and the Prince pursued him. To seal away The Raven, the Prince shattered his own heart with his sword.

Drosselmeyer had however written about himself before he died, and thus continued to control events despite his death. When he sees a duck watching the sad, heartless Prince Mytho dancing on the water, Drosselmeyer decides to let the story take a new course. He gave the duck a magical necklace, which transforms her into a human girl named Duck (Ahiru in the manga), so that she might find a way to help the Prince. As long as she possesses the necklace with its red, egg-shaped jewel, she can transform into a girl. If she quacks, she returns to being a duck; she can revert to human form if she comes into contact with water.

Now a gawky pre-teenager, Duck becomes Mytho's classmate and takes ballet classes with him. She grows deeply infatuated with Mytho, now a popular boy in their school, eventually learning of his shattered heart. To help recover his heart's pieces, Duck's necklace also enables her to transform into the beautiful Princess Tutu — a mature, expert ballerina with special powers. The necklace's jewel glows red whenever a heart shard is nearby, and these shards have lodged themselves in people with strong emotions, which the heart shard magnifies. To cure these people, Princess Tutu invites them to dance with her, communicating without words to help them better understand and overcome their feelings. Since their heightened emotions are a result of the heart shard within them, they are freed of this artificial intensity when Princess Tutu removes the shards and returns them to Mytho.

When Mytho's girlfriend Rue realizes that Tutu is restoring Mytho's heart, she grows worried that he will fall in love with someone else. This unleashes her power to transform into Princess Kraehe, the dark counterpart to Princess Tutu and who is mistakenly thought to be The Raven's daughter. With her powers, Kraehe tries to stop Tutu and capture a heart shard herself, so that she can free her father The Raven. Mytho's childhood friend Fakir also attempts to stop Tutu out of fear that if Mytho's heart were mended, the story would progress and he would have to shatter it again to stop The Raven. However, it becomes clear that Mytho wants his heart to be restored, and Duck persists despite Kraehe and Fakir's interference.

As the story unfolds, Fakir learns that he is a descendant of Drosselmeyer, which explains Fakir's ability to alter reality through writing stories. He initially resists using those powers as when he was a child, these did not help him. A swarm of ravens attacked the town, and wanting to help, Fakir wrote a story where the ravens came for him and he fought them off. Unfortunately, only part of the story came true: the ravens attacked his home but Fakir was unable to stop them, and his parents died protecting him. Duck eventually convinces Fakir that he must write again in order to save Mytho, and Fakir's feelings towards Duck change from his initial suspicion and contempt. He becomes reluctantly tolerant, until finally he has affection for Duck as he writes a story for her, to aid her when she falls into despair.

Drosselmeyer attempts to lure Duck into a selfish choice, but she refuses, accepting that she is in reality a duck and her status as a human girl and Tutu is temporary. Uzura, the toddler-like reconstitution of Drosselmeyer's assistant Edel, meanwhile finds the mechanism driving the story and turns it backwards, revealing secrets of the past. Kraehe then learns that The Raven is not her real father and that she was kidnapped by ravens as a child.

Impatient with Kraehe's failure to secure him a heart shard, The Raven attacks the town, covering it in darkness. Kraehe reverts to being Rue and attempts to help Duck, only to be captured by The Raven. Duck asks Fakir to write one last story for her, and as Tutu, she restores the final shard of Mytho's heart. This last shard is Duck's enchanted jewel, and when she returns it, Tutu vanishes. The Raven then turns the townsfolk into ravens that attack Duck, and Mytho is overwhelmed by The Raven's minions trying to steal his heart. Rue meanwhile is unable to escape The Raven's clutches because of her despair. Seeing no other solution, Prince Mytho prepares to once again shatter his heart with his sword. Despite being in animal form, Duck refuses to accept this outcome and thus begins to dance to the astonishment of all.

The ravens battle Duck mercilessly, and Fakir starts to write the story Duck requested, finding that Drosselmeyer's story dominates everything he does and is forcing Drosselmeyer's intended tragedy. Fakir must also fend off the townsfolk who are coming to chop off his hands out of fear he will follow the same abusive path as Drosselmeyer. Gradually gaining control of the story, Fakir transforms it into a positive, inspirational tale of how a little duck, no matter how badly she was injured by the ravens, continued to dance because of her unwavering hope. Each time Duck gets knocked down, she gets up to dance once more.

Fakir and Duck's perseverance gives Mytho and Rue the strength to finally destroy The Raven. This lifts the darkness, restores the townsfolk to normal, and forever frees Rue from serving The Raven as Princess Kraehe. Mytho, Rue, Fakir, and Duck then restore the town itself by tearing down the machine in the clock tower that mechanically wrote stories and enabled Drosselmeyer to control events. Drosselmeyer admits defeat, and moves on with Edel to create new tales elsewhere, while Mytho and Rue marry and return to Mytho's original kingdom. At the end, Fakir is shown carrying Duck on his arm wherever he goes. In the closing scene, he is seen sitting on a dock, writing whilst Duck floats and dozes nearby in the lake. The narrator ends with, “And there was another man who began writing stories. That story, full of hope, has only just begun.”