The opening episodes establish a world where exploring new planets gets people killed in ways the show doesn't shy away from. Characters carry real weight, Matoi's amnesia isn't a plot device, it's the center of everything, and watching her piece together what she is costs her every time she remembers. By midpoint the narrative momentum stumbles, but the character work Quna and Klariskrays do in the background keeps pulling you forward into a mystery the show earns rather than explains away.

The colony fleet Oracle roams space in search of a planet where its people can settle, and the ARKS organization explores new worlds while defending Oracle and other planets. Its enemies are monstrous creatures called Darkers, directed by the villainous Dark Falzes. During his graduation, young cadet Ash sees the ceremony broken up by an attack and finds himself caught in a conflict on a universal scale. Adapted from SEGA's online role-playing game, this sci-fi action TV series covers the first three story episodes of the game and adds original material of its own.