Synopsis: Since the planet Sargol did not look like a rich trading planet, the free-traders got the contract to trade with the cat-like inhabitants. And after initial negotiating difficulties, they discovered the key to mastering trade relations with them. But the discovery of rare jewels puts them in competition with a major trading company. And when on their return trip, most of the crew falls ill to a possible plague, it falls upon 4 of the youngest team members to find the real problem, solve it, and convince the world that they should not be destroyed as a plague ship.