"Yes, but wait. That fellow had nothing to go wrong about. He was tremendously successful, rich, happily married, and highly respected for his outstanding integrity. Yet he could hardly have been kidnaped, as there has never been a ransom demand. Nor has there ever been such a demand in any of the other cases similar to it. "The next case to be partially explained was that of the disappearance of the president of the Jupiter Trust Company at Ionopolis. All the most vital secrets of that bank turned up later in all parts of the civilized system. We nabbed some peddlers, but it was the same story as with the first gang. The facts are all here in this jacket. After a little you can read the whole thing in detail." "Uh, huh," grunted Neville, "I'm beginning to see. But why _me_, and why at Pallas?" "Because you've never worked in the asteroids and are not known here to any but the higher officers. Among other secrets this ring has, are a number of police secrets. That is why setting traps for them is so difficult. I haven't told you that one of their victims seems to have been one of us. That was Jack Sarkins, who was district commander at Patroclus. He received an apparently genuine ethergram one day--and it was in our most secret code--telling him to report to Mars at once. He went off, alone, in his police rocket. He never got there. As to Pallas, the reason you are here is because the place so far is clean. Their system is to work a place just once and never come back. They milk it dry the first time and there is no need to. Since we have no luck tracing them after the crime, we are going to try a plant and wait for the crime to come to it. You are the plant." "I see," said Neville slowly. He was interested, but not enthusiastic. "Some day, somehow, someone is coming here and in some manner force someone to yield up all the local dirt and then arrange his disappearance. My role is to break it up before it happens. Sweet!" "You have such a way of putting things, Neville," chuckled the colonel, "but you do get the point." He rose and pushed the heavy folder toward his new aide. "Bone this the rest of the afternoon. I'll be back." * * * * * It was quite late when Colonel Frawley returned and asked Neville cheerily how he was getting on. "I have the history," Neville answered, slamming the folder shut, "and a glimmering of what you are shooting at. This guy Simeon Carstairs, I take it, is the local man you have picked as the most likely prospect for your Master Mind crook to work on?"