In the beginning of the third game in the series, you arrive on Tomahna, which is Atrus, Catherine, and Yeesha's new home.
As you and Atrus are about to leave for a visit to Releeshahn, an age he recently wrote as a new home for the D'ni, a man (Saavedro) links to the room, steels the Releeshahn book, sets the room on fire, and links away. You follow him to an Age called J'nanin, one that Atrus originally wrote to teach his sons how to be competent in an Age by themselves. You travel to three other ages, one filled with machines, another with flora and fauna, and one needing energy for the items on the Age to operate. In these ages, you collect three symbols in order to keep following Saavedro. You learn that he is seeking revenge on Atrus because he believes that Atrus's sons destroyed his home. See the multiple endings section for the endgame.