A moment's silence. Then the Russian said, "Assuming one of us is an alien—not that I believe Beveridge's fanciful story—how would we know? Until Earth is destroyed, that is?"
"That's just it," said Lal gloomily. "We wouldn't know. Not until it was too late."
What began as Beveridge's dinner-table joke soon became an earnestly-held belief. Perhaps it was the strain of life aboard the satellite, 10,000 miles above the Earth's surface. Perhaps the tensions of a year's isolation from the rest of humanity were taking their toll. But, from a dinner-table jest, the concept soon became a source of serious discussion. And tension.
Tension wrapped cold fingers around them as the days passed. They agreed to operate in teams, never to let one out of another's sight, always to keep constant watch ... for there was no way of telling which of them harbored in his body or his mind Earth's potential destroyer.
Two days passed this way, and a third. Then Lal went for a walk in space—without a suit.
"He cracked," Gregson said, staring at the Indian's corpse. "This crazy alien business—it just broke him apart."
"Yes," Lasseux said moodily. "The tension ... the looking and spying ... he couldn't take it any more. Our first casualty. But not the last, I fear."
Beveridge and Gregson brought Lal's body in—it was orbiting around the Wheel—and a brief funeral service was conducted. The Indian's body was fed to the atomic converters that ran the station and consumed in an instant's blaze of light.