He tugged on his prominent nose, watching the preposterous data appear on the displays. The printer beside him hummed, producing a hard-copy graphic representation of the raw numbers, and he tugged harder. According to his demented instruments, someone must have been a busy little beaver down there. It looked for all the world as if a vast labyrinth of tunnels, passages, and God knew what had been carved out under eighty kilometers of solid lunar rock!

He allowed himself a muttered imprecation. Less than a year from mission date, and one of their primary survey systems—and a NASA design, at that!—had decided to go gaga. But the thing had worked perfectly in atmospheric tests over Nevada and Siberia, so what the hell had happened now?

He was still tugging on his nose when the proximity alarm jerked him up in his couch. Damnation! He was all alone back here, so what the hell was that?

"That" was a blip less than a hundred kilometers astern and closing fast. How had something that big gotten this close before his radar caught it? According to his instruments, it was at least the size of one of the old Saturn V boosters!

His jaw dropped as the bogie made a crisp, clean, instantaneous ninety-degree turn. Apparently the laws of motion had been repealed on behalf of whatever it was! But whatever else it was doing, it was also maneuvering to match his orbit. Even as he watched, the stranger was slowing to pace him.

Colin MacIntyre's level-headedness was one reason he'd been selected for the first joint US-Soviet interstellar flight crew, but the hair on the back of his neck stood on end as his craft suddenly shuddered. It was as if something had touched the Beagle's hull—something massive enough to shake a hundred-ton, atmosphere-capable, variable-geometry spacecraft.