When a mysterious signal appears in a remote valley, researcher Mara Linton discovers an ancient tower created by a distant civilization to test whether intelligent worlds choose curiosity over fear. Through a series of encounters with an entity called the Echo, humanity learns that the tower is not a weapon or a warning but a question asking whether a civilization is ready to grow. As Earth begins to change and embrace cooperation and discovery, Mara realizes that the true signal to the universe is humanity’s willingness to keep learning.
