The Solar Queen, a spaceship, has gained a trading agreement on the planet Sargol. They are building a relationship with one of the races on the planet, the cat-like Salariki, who learn that the ship is carrying catnip and other plants from Terra that are unknown to them. The traders exchange what little of the plants they have for the rare and valuable Koros stones and collect a native red-colored wood to exchange at home. A few days after leaving the planet, numerous members of the crew suffer from attacks, starting with severe headaches and ending in a semi-coma state. Upon exiting hyperspace, they discover that they are pariah and have been declared a plague ship... This is the second installment in Norton's Dane Thorson/Solar Queen series.