A navigational 'accident' finds Ben Grissam marooned around the sea world 'Saline'. He boards an abandoned alien mining vessel where, with the help of the hologram Science Officer, he solves the mystery of the crews disappearance. However, the intrigue continues when the crew's home world Hebros is threatened by the warlike A'rath. Ben must find a way to defeat them in order to save Hebros.
Nebula Award Nominee. The crew of Moonbase Columbus make an amazing discovery on the far side of the Moon—a massive alien structure is erecting itself, built up atom by atom by living machines, microscopically small, intelligent, and unstoppable, consuming everything they touch. The mysterious structure begins to expand and take shape, and its creators begin to multiply.
Diana hears the voice of Moosevan, an entity who inhabits a distant planet, in her head. Her world is threatened and she wants Diana’s help. Yuri believes her, though he's usually drunk in charge of a ten inch reflector and has a bizarre theory about the movement of the asteroids.
Then two cosmic intelligences decide to help. They may understand the Universe, but mere mortals are beyond them.