He worked on bigger stuff. He didn't try just everybody. He picked his signers with care. He slept until nine every morning and he and Penelope played two-handed bridge at a tenth of a point a point until midnight. He felt sorry for the poor suckers who had to get out at sunup and tread the sidewalks until dark to get enough points to satisfy Central. They were working like slaves, while he was living the life of Point-a-Minute Charlie. It was a lovely existence. He forgot about Penelope's slip for thirty-five thousand. He could almost pay it off anyway. Then came the day when he pulled his grand coup. He spent a week planning it, with Penelope's shrewd advice. He remembered what she had said about the man on the ladder in the nineteen-forties. He sandpapered his back and painted an irregular spot with merthiolate and iodine, and practiced twisting his back until it looked out of shape. Then he went out and watched for an absent-minded, nervous, excitable-looking man to try his next effort on. Penelope's biggest advice was, "Preparation is half the points," so it was three days before Mark found the right person. After he found him it was very simple. He signaled Penelope to follow, and then he walked behind the man until they came to a high curb. Mark moved out to the left. The man started to step up on the curb. Mark darted across in front of the man just as the man raised his foot. Mark managed to stumble exactly in front of the man. His arms went out and one hand caught the little man's leg. The little man fell squarely on top of him, assisted by a slight push from Penelope. Mark groaned heart-breakingly. In a moment there was a crowd. The little man was getting up, bewildered, and automatically trying to dust off his type K suit. Mark lay half on the curb, half off, squirming like a broken-back snake. "My back," he moaned piteously. "Oh, my back." The little man seemed paralyzed at the enormity of the thing he had done. He stared at Mark and Mark squirmed harder and moaned louder. Then Penelope hobbled up and pulled Mark's shirttail out of his trousers. The iodine spot on his back looked yellow and purple, and there were gasps from the crowd. "He did it!" Mark said, glaring accusingly at the little man. "He tripped me. He tripped me and broke my back!" Penelope was putting on a good act too, crying and wringing her hands and moaning. "My poor boy!" she said, over and over. A woman in the crowd came up and made a very expressive raspberry in the little man's face. The little man was not only bewildered; he was frightened. Mark adjudged the time had come. "Points for my broken back!" he cried. Penelope held out a slip to the little man. He signed it dazedly, then he slipped out of the crowd, while three men picked up Mark and laid him tenderly in Penelope's reclining wheel-chair. Mark could hardly contain himself. As soon as they were safely out of sight he said excitedly, "Let me see the slip."