"Squirrel Nutkin" is a children's book written and illustrated by Beatrix Potter. First published in 1903, it tells the story of a young squirrel named Nutkin who is mischievous and adventurous. He and his friends visit an island to gather nuts but annoy Old Brown, the owl who lives there, by teasing him. The story highlights themes of curiosity and the consequences of one's actions. Nutkin's playful behavior ultimately leads to a confrontation with Old Brown, teaching readers about respect and caution in nature. The charming illustrations and engaging narrative make it a beloved classic in children's literature.