Interstellar patrol

The crew of the ship were marooned on a planet with no ship repair facilities, where the well-meaning schemes of social engineers had created a nightmare of battling gangs. They had their own invention with them-an emotional amplifier, which could cause anyone to feel a heightened emotion, but this wasn't useful at first. If they heightened the locals' sense of pride, they took pride in becoming better criminals. So they pretended to be the Royal Legions, sent by a distant star kingdom in pursuit of an all-powerful villain who was hiding on the planet. Things were going better than they could have hoped, and the planet was rapidly becoming civilized . . . and then the real Royal flagship showed up. They thought they were doomed-but instead they were told they had shown just the type of initiative and intelligence that the new arrivals were looking for. So they were inducted into the Interstellar Patrol. And that was just the beginning. . . .