The spinship "Helix" has not yet reached a suitable destination when it receives a distress signal from a binary star system. Four of the five shipboard AI (apparently formerly of the TechnoCore; in characteristic Simmons fashion, each is patterned after a famous literary figure, in this case, Japanese: Saigyo, Lady Murasaki, Ikkyu, Basho, and Ryōkan) decide that the call is worth investigating, not least because of the further anomaly that the orbital forest around the lesser of the two stars, which the AIs intend to resupply their ship from, is of neither Ouster nor Templar construction, though they may have settled on it.