Three hundred years ago, a strange and seemingly invincible alien ship visited the Sakhran Empire. Exactly what happened is unclear, because the events were only recorded in the Book of Srahr, a text only Sakhrans are allowed to read. After the ship left, the Sakhran Empire went into a slow but irreversible decline.
Three centuries later, the Sakhrans have been assimilated into the larger interstellar empire known as the Commonwealth, when suddenly the strange, immensely powerful ship returns. The Commonwealth dispatches an Outsider, one of only nine in its ultimate class of warships,