"Turquoise Days" is a story which appears in the collection Diamond Dogs, Turquoise Days.
This story is set in the year 2541 on the planet Turquoise, a Pattern Juggler world which is also the site of a human colony. It has been settled by humans for a considerable period of time, but is technologically far behind the rest of humanity. The protagonist, Naqi, loses her sister at the start of the story when she swims with the Pattern Jugglers and is absorbed by them. Later on, a lighthugger, the Voice of Evening, visits the planet, the first lighthugger to do so in a long time. They're welcomed by the local government, and among the people on the lighthugger are a crew of scientists intending to study the Pattern Jugglers.
Naqi gets suspicious when the "scientists" demand access to the massive Juggler research station named the Moat. When one of the foreigners' party, who was already under suspicion, sneaks onto a boat and begins to poison the Pattern Juggler nodes, previously thought to be toxin-resistant, Naqi immediately tries to follow him, but is unable to catch up in her rotting emergency boat. When she returns to the main Moat structure and finds that all of the research crew has been murdered by the spacefarers, she quickly escapes the moat with a high-speed boat docked on the outside wall, and resumes her pursuit of the runaway spacefarer, who is also being hunted down by the others of his party.
When Naqi finally catches up with him, he reveals that the "scientists" were in fact members of a lunatic organization whose dead leader had stored his thought patterns with the Jugglers on Turquoise, and that they intended to incorporate him into all of the many-thousand strong army of followers that were waiting in orbit on the Voice of Evening. He then tells her that he was the only resistance agent able to infiltrate the Voice of Evening and that he planned to spread the rare Juggler toxin into the sea, thus destroying all of the patterns stored within the Jugglers' memory. The agent says no one knows where the toxin originated, though he mentions several rumours, one of which indicates that it had been found in the top of the Blood Spire from "Diamond Dogs".
Knowing that the release of the toxin would destroy all the other minds stored in the juggler sea as well, including her sister, Naqi refuses to allow him to destroy the Jugglers, and instead warns the Jugglers, as well as her sister, by swimming in the sea. Naqi kills the agent when he manages to release the toxin anyway.
However, it transpires that the Jugglers had developed a resistance to the toxin after the first vial that had been slipped into a contained portion of the Moat, and the overall collective is unharmed. However, the Juggler life-forms around the planet begin to attack and destroy all human settlements, effectively eradicating the threat as well as the human presence on Turquoise. In the end, Naqi takes a final swim in the ocean, and joins her sister in the Juggler collective.