"Run!" Arlen cried. "And look out for the python."

Arlen sprang forward. He heard a leathery scrape ahead of him. It was the serpent. He dodged back. Suddenly from behind came a hoarse cry.

Arlen turned, ready to blast the Venusian that had shouted. But the Venusian did not attack. Instead, it darted forward, and with a flying leap it sprang upon the python. A roar came from the Venusian's throat.

It was Gheal. Arlen would have recognized the voice anywhere.

The faint glow from the volcanoes showed him the edge of the plateau.

Renzu was screaming behind him and he heard the pad-pad of the running feet of the three remaining Venusians. But Arlen was clear and McFerson was running beside him.

Arlen took his flashlight from his pocket and used it to follow the narrow ledge down the mountain into the canyon. Behind the two men, sounds of pursuit grew fainter.

"We're safe," Arlen said, slackening his pace. "Renzu won't follow us as long as he knows we're armed."

"He's armed, too," McFerson said.

"He wants our bones too badly to use a disintegrator on us," Arlen laughed.