But then he sensed that something more was about to happen than just the car arriving. It was a change in the expression of the face behind Mary that gave him the cue--a widening and side-wise flickering of the cold eyes, the puckered lips thinning into a cruel smile. The Essex shifted into second and, without any warning, accelerated. Simultaneously, the woman behind Mary gave her a violent shove. But at almost exactly the same instant, Jack ran. He caught Mary as she sprawled toward the gravel, and lunged ahead without checking. The Essex bore down upon them, a square-snouted, roaring monster. It swerved viciously, missed them by inches, threw up gravel in a skid, and rocked to a stop, stalled. * * * * * The first, incredulous voice that broke the pulsing silence, Jack recognized as Martin Kesserich's. It came from the car, which was slewed around so that it almost faced Jack and Mary. "Hani, you tried to kill her! You and Hilda tried to kill her again!" The woman slumped over the wheel slowly lifted her head. In the indistinct light, she looked the twin of the woman behind Jack and Mary. "Did you really think we wouldn't?" she asked in a voice that spat with passion. "Did you actually believe that Hilda and I would serve this eighteen years' penance just to watch you go off with her?" She began to laugh wildly. "You've never understood your sisters at all!" Suddenly she broke off, stiffly stepped down from the car. Lifting her skirts a little, she strode past Jack and Mary. Martin Kesserich followed her. In passing, he said, "Thanks, Barr." It occurred to Jack that Kesserich made no more question of his appearance on the island than of his presence in the laboratory. Like Mrs. Kesserich, the great biologist took him for granted. Kesserich stopped a few feet short of Hani and Hilda. Without shrinking from him, the sisters drew closer together. They looked like two gaunt hawks. "But you waited eighteen years," he said. "You could have killed her at any time, yet you chose to throw away so much of your lives just to have this moment." "How do you know we didn't like waiting eighteen years?" Hani answered him. "Why shouldn't we want to make as strong an impression on you as anyone? And as for throwing our lives away, that was your doing. Oh, Martin, you'll never know anything about how your sisters feel!" He raised his hands baffledly. "Even assuming that you hate me--" at the word "hate" both Hani and Hilda laughed softly--"and that you were prepared to strike at both my love and my work, still, that you should have waited...." Hani and Hilda said nothing. Kesserich shrugged. "Very well," he said in a voice that had lost all its tension. "You've wasted a third of a lifetime looking forward to an irrational revenge. And you've failed. That should be sufficient punishment."