Penelope is a three-year-old blue koala with a red nose, a curious and lively personality, and a tendency to be a little absent-minded. She lives in a cheerful, colorful world with her family, which includes her mother, father, and a soft blue rabbit named Dou Dou who is her constant companion and favorite stuffed animal. The series follows her daily adventures as she navigates the small but significant milestones of early childhood, from getting dressed by herself and learning to ride a bicycle to going on a picnic and baking cookies with friends. Each five-minute episode captures a small slice of her life, focusing on the innocent mistakes and discoveries that come with being very young, such as planting candy instead of seeds in a flowerpot, losing a sock while trying to clean her room, or accidentally pulling the plug while searching for Dou Dou in a bubbly bath. Her friend group includes Lily Rose, Cezarine, Aladin, and Strombouli, and together they attend kindergarten, play hide-and-seek, and explore the world around them under the gentle guidance of patient grown-ups like her grandparents and teacher. The narrative style is gentle and observational, with a narrator often helping to frame Penelope's thought process as she tackles everyday challenges like saying hello and goodbye, learning colors and shapes, or understanding why she cannot stay up all night to play. While most episodes focus on the simple, relatable joys and minor mishaps of preschool life, notable narrative arcs include Penelope preparing for major holidays like Christmas and Carnival, celebrating her grandfather's birthday, and, in later seasons, adjusting to the arrival of younger siblings as she becomes a big sister to twins named Eustache and Philomène. The series maintains a soft, storybook aesthetic that faithfully adapts the original picture books, emphasizing warmth, curiosity, and the gentle reassurance that mistakes are a natural and even wonderful part of growing up.