The Cat Returns (2002)
Based on the 2002 manga Baron: The Cat Returns by Aoi Hiiragi which is a spin-off of Whisper of the Heart.
Haru Yoshioka is a shy but noble high school student who has a suppressed ability to talk with cats. One day, she sleeps through her alarm is late for class and is embarrassed for trying to sneak in. While walking home, she admits to her friend Naoko that she actually likes a boy in her class named Machida but is too shy to ask him out. Naoko then reveals that he has a girlfriend. While walking, the girls notice a Russian Blue odd-eyed cat with a gift box crossing the street, Haru saves the cat from being hit by a truck. The cat stands up and thanks Haru for saving him but Haru is too surprised to even respond. Later, she tells her mother and her mother remembers how Haru once said she could talk to cats especially when she was younger. Haru then recalls when she was younger and gave a stray cat some fish crackers. That night, the king of the Kingdom of Cats comes with a parade to thank Haru for saving Prince Lune, the cat she saved earlier, who is the Cat King’s only son and Prince of the Kingdom of Cats. As thanks, the Cat King gives Haru a scroll which has a list of gifts she'll receive tomorrow, Haru thanks them and the King goes on his way.
The next morning, gifts are showered upon Haru and Naoko including Lacrosse sticks, cattails, neighborhood cats, catnip, and boxes full of mice. After reading the scroll during break, Haru now understands the Cat Kingdom was behind everything. The King’s servant pays Haru a visit but she scolds him for all the gifts and how they haven't made things better for her. As a result, he invites her to the kingdom and reveals that she is being offered the Prince's hand in marriage. Her mixed reply is mistaken as a yes and tells her he'll pick her up tonight.
Wanting none of this, Haru hears a kind female voice which tells her to seek out Muta, a large white cat, and to get directions to the Cat Business Office from him. Muta leads her there to meet Baron Humbert von Gikkingen, who is a cat figurine given life by the work of his artist, and Toto, a stone raven who comes to life much like the Baron. Soon after meeting them, Haru and Muta are forcefully taken to the Kingdom of Cats by the King’s servant, leaving Toto and the Baron in the human world to follow the group from the air. They find the entrance to the Kingdom of Cats: five lakes forming a cat's paw.
Haru is treated to a feast at the castle of the Cat King. She begins to slowly turn into a cat with tan paws, ears, nose, tail and whiskers, though she still remains mostly human. The King hopes that she will make a suitable bride for the Prince. At the feast, a disguised Baron dances with Haru as part of the entertainment. He reveals to her that the more she loses herself in the kingdom, the more cat-like she will become, and that she has to rediscover her true self. When the Baron is discovered and is forced to fight the guards, he and Haru are helped by Yuki, a white cat maiden in the palace who had previously tried to warn Haru to leave the Cat Kingdom. After Yuki shows them an escape tunnel, Haru, the Baron and Muta move through a maze to a tower, which contains a portal to Haru's world. The King goes through a series of efforts to keep them in the kingdom long enough for Haru to remain trapped in her cat form; his ultimate plan is still to force her to become his daughter-in-law.
Prince Lune and his guards return to the Cat Kingdom, revealing the King was not acting on his behalf and that he planned on proposing to Yuki. Muta is revealed to be Renaldo Moon, a notorious criminal in the Kingdom, having devoured a whole lake of fish in one session. Haru learns that the strange voice who had advised her to go to the Cat Business Office was Yuki's. In her childhood, Haru had saved Yuki from starvation by giving her the fish crackers she was eating, and thus, Yuki has now repaid her kindness. After she rejects the King's marriage proposal outright, Muta proceeds to help her escape from the King's soldiers.
Eventually, the Baron, Haru and Muta escape the cats' realm, with the aid of Prince Lune and Toto, and Haru discovers her true self, telling the Baron how much she has come to like him. He tells her the doors of the Cat Business Office will be open for her again if the need ever arises. Haru returns to the human world with more self-confidence; after learning from her friend, Hiromi, that her former crush has broken up with his girlfriend, she simply replies that it doesn't matter anymore.
TRIVIA
Muta is based on Ushiko, the resident cat that wanders around Studio Ghibli’s offices.
When crafting the story, Miyazaki imagined this would have been a story written by a grown up Shizuku from Whisper of the Heart who would have published it under the title Baron: The Cat Returns.