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The movie is a slow-moving yet fascinating portrayal of rural Japanese life. A university professor moves with his two daughters to a new house near a forest, while his wife recovers from tuberculosis in a rural sanitorium. His daughters discover "dust bunnies" (or "soot sprites"), which leads them to find some Totoro creatures. Not everyone can see the spirits of the forest, only the pure in heart. Four-year-old Mei is enchanted with them and determined to find the king of the forest. When she gets lost bringing an ear of healthful corn to her mother at the sanitorium, older sister Setsuki runs everywhere searching for her, finally seeking Totoro's help. He is delighted to be of assistance and with his help, Mei is quickly found.
The movie features the "cat bus", a grinning feline bus called by Totoro to transport Mei and her older sister to the sanitarium to see their mother. It whisks Mei and Satsuki over the countryside to visit their mother in the sanitorium. Inasmuch as it is a grinning cat, it can be compared to Lewis Carroll's Cheshire cat. The large Totoro creature himself has become the mascot character for Studio Ghibli, as well as an iconic character who is manifested in many other anime movies.