When humanity spread to the stars, Earth was left behind and all but forgotten. All that remains is the cult "Terraism" which has become increasingly popular in the former Free Planets Alliance and the former Phezzan Dominion. Julian begins his long journey to Earth where he hopes to learn the goals of the Terraism cult.
Similar to episode 40 of the series, much of the backstory is revealed in this episode. In particular, the history of Earth from the early 21st century through the 29th.