Humanity has united multiple alien races to form the "Interstellar Federation" with the purpose of "exploring the unknown and achieving peace and common prosperity." The protagonist Katherine Raven serves as the captain of the starship "Eternal". This latest scientific exploration ship is sailing to the newly discovered "rift galaxy" on the edge of the Milky Way - a mysterious galaxy divided into fragments by dark matter rifts. It is said to hide ancient secrets that subvert the understanding of the universe.
