Tom Tom is an Australian Aboriginal boy orphaned by settler violence and stranded on the same island as the Robinson family. He survives under the coarse guardianship of Captain Morton. Harboring deep distrust towards Europeans from past enslavement, Tom Tom avoids the Robinsons and steals food from their garden, driven by survival and resentment.

His isolation fractures when caught stealing melons, forcing initial interaction with the family. Resistant at first, he gradually bonds with Flone (Becca in English dubs), whose persistent kindness bridges the cultural gap. This connection leads to his integration into the Robinson household, where he accepts food, shelter, and informal education in literacy and mathematics.

Tom Tom shares vital survival knowledge, demonstrating superior expertise in local flora, fauna, and hunting techniques. He teaches the Robinsons effective methods for resource utilization and animal taming, significantly enhancing their ability to thrive.

When volcanic activity threatens the island, Tom Tom labors alongside the family to build the escape vessel. After reaching Australia, he finds shelter with the Robinsons until Morton secures passage. He departs with Morton as Emily travels to England, exiting the narrative.