The Cleansing

Orion Federation's Chief Deputy Arbiter, D'zeekr Qrono arrives to Orb E-3 to investigate the disappearance of a fellow cosmic voyager, Ea Andromeda. However, upon landing he's telepathically contacted by a sentient species known as the Adumen, who offer to help him solve the case in return for his help to fight against the civilization that has oppressed them for a millennia, the city of Atlantis.