Over the past few decades an uneasy peace has held between Earth and the Ilaxi, but the Ilaxians have been making threatening incursions over the border and into Terran space recently and, as a result, Terran forces have been placed on High Alert. When Historian Calvin McCauley is invited to study a massive and unique alien structure found on the borders of Terran and Ilaxi space, he quickly becomes embroiled in a conspiracy to exploit the artifact for sinister purposes.