Dirrul's memory after that was a vague patchwork of unrelated episodes. He saw huge saddled reptilian bipeds dragged out of the concealing brush. The captives were bound in the saddles and the black-robed figures mounted behind them. Later two of the men pulled Dirrul up and tied him across a saddle too. At a sickening gallop the caravan moved away from the green highway, striking out over the purple plain. For a while Dirrul lost rational control of sensation. He felt but without understanding. His brain pulsed in a continuous terror that seemed to resolve itself into sound--a continuous high-pitched scream coming from within his own mind. His body throbbed with pain and nausea wrenched emptily at the muscles of his stomach. But he could not sort out the feelings, classify them or adjust to them. At the edge of the plain the caravan turned up a steep rocky trail which led into the ragged range of mountains banked behind the Vininese city. They came to a stop in a stony ravine, concealed beneath a tangle of gigantic purple-leafed vines. Dirrul's captors dismounted and removed their black cloaks, hiding them among the rocks. Underneath they wore the warm gray skintight workers' clothing of Vinin. The majority left their animals tethered to the roots of the vine and began the steep descent on foot to the city. Only three remained behind to guard the prisoners. They built a small fire and prepared food, serving the hot sweet chunks of white meat in large wicker baskets. As soon as Dirrul discovered that he could stomach the food he wolfed his share hungrily. The guards brought him more. He felt better. Except for the sing-song ringing in his head he might have been able to think clearly enough to evaluate his own position. But that could be done later. He was overcome by an immense drowsiness. He relaxed and slept. VI A shrill scream woke him with a start of horror. His captors had taken him from his saddle and propped him against a mound of rocks, along with the other prisoners. His muscles were numb and dead, so limp it was almost impossible for him to turn his head. Faintly the whirring terror whispered in his mind. Dirrul's eyes focused slowly on the clearing. One of the prisoners had been carried there, close to the fire. It was Glenna. Two of her captors held her while the third bent over her head, probing her ear with a sharp instrument. His arm moved. Glenna screamed and fainted. For a moment Dirrul saw the side of her face smeared with a spreading stain of blood. Then nausea swept over him. When he opened his eyes again the three men were working over another prisoner at the fire. Vaguely Dirrul knew he had to escape. He forgot the Movement--he thought of nothing any loftier than his own personal survival. The idea was elemental, built upon the simplest sort of observation and hypothesis.