One day, as literate Mummy Duck sits reading a book next to her three duck eggs, a larger egg rolls down a mountain and lands in the nest. Mummy Duck cares for the egg along with the others. After they all hatch, Mummy Duck has four offspring: the ducklings—Packo, Jacko, and Quacko—and a kind little crocodile named Croco. Croco loves his life among his feathered family, and they respond to him and his helpfulness with returned love and gratitude. The calm comes to a halt one day when "a big, bad crocodile" enters their environment with the intention of eating the ducklings. The big, bad one challenges Croco to act like a crocodile and throw the ducklings to him to eat. Croco agrees, but throws rocks instead and breaks the other crocodile's teeth. The injured crocodile runs away, "never to be heard of again." Croco then promises his family that he will always protect them and becomes the hero, "CrocoBoy."
This unique tale is the introduction to a series of children's books planned to feature the courageous crocodile. Bold illustrations by Rumar Yongco display the story in dazzling color. The tale, which has been developed by a daughter and mother, is intended to reflect young Aanya Savi's conviction that "even animals like crocodiles and sharks, that are painted as vicious killers, are only living their lives." The eccentric interplay between species—the crocodile egg landing in a duck's nest, and the bad crocodile coming to eat the ducklings and being injured—can be seen as examples of animals' attempts to adapt to survive in ecosystems that have been disrupted by humans.