The film serves as a tribute to pulp magazines and sci-fi adventures of the early 20th century. It explores themes of environmentalism, father-son legacies, and the importance of adapting to change to ensure a sustainable future for the next generation.

Twenty-five years later, Avalonia has become a technological marvel powered by Pando. However, the plant is mysteriously dying. Searcher, now a farmer, joins a mission led by Avalonia's president, Callisto Mal, to travel deep underground to the plant's roots to save it. Along the way, Searcher discovers that his son Ethan and his wife Meridian have stowed away on the ship.

Set in the fictional land of Avalonia, the narrative begins with Jaeger Clade and his son Searcher attempting to cross a massive mountain range that encircles their civilization. During the trek, Searcher discovers a plant called Pando that emits electricity. While Searcher believes they should stay and cultivate the plant, Jaeger is obsessed with continuing the journey and disappears into the wilderness.