The protagonist of Atlantis: The Lost Empire is Milo Thatch, an eccentric linguist working in 1914 who believes in the existence of the ancient city of Atlantis. He is called to adventure when he is recruited by the wealthy philanthropist Preston Whitmore to lead an expedition to find Atlantis. Milo accepts the call and crosses the threshold into the unknown world when the expedition discovers Atlantis. He must overcome challenges like learning to navigate the advanced technology of Atlantis. Milo acquires new skills and knowledge of Atlantis, helping him succeed in finding the crystal that saves the city and returns home a true hero.