"That a man of Mars stood on this very spot."
"All I see are boot prints."
"Examine the markings more closely. Do the heels not consist of the Greek letter Mu?"
Remo looked closer.
"Yeah, now that you point it out, the tread is a stack of M's. So what?"
"Mu's. Men from Mars. Clearly the Martians are wearing Martian-made boots."
"Come off it. If there were Martians, they wouldn't advertise their existence with brand-name boots. Besides that, the Martians don't use the English alphabet."
"So you admit Martians do exist?" said Chiun loftily.
"No, I don't."
"Even with the proof etched in the red dust at your feet?"
"Look, let's collar this guy and find out if he's a Martian or not."
"I will agree to this. Let the Martian decide this argument."
"Fine. Let's go."
The footprints led through eroded red rock and sand until, without warning, they just stopped.
"Where'd they go?" Remo said, looking around.
Chiun frowned. "They stop."
"I can see that. How is that possible?"
"It is simple. The Martian entered his space chariot at this spot and was whisked back to his home desert."
"No sale. It don't see landing-gear marks."
"Further proof!" Chiun crowed.
"Of what?"
"That Martians truly exist."
"How?"
"You would not look for the marks of their space chariots if you did not secretly accept their existence," Chiun sniffed.
Remo started to throw up his hands, decided against it and knelt instead. "Something's wrong here," he muttered.
"That is obvious," Chiun sniffed.
"No. This patch of ground. Feel it with your sandals."
Chiun scratched at the red sand experimentally.
"It does not shift like loose sand," he said, papery lips thinning.
"Yeah. It's fixed. Like the sand grains are cemented down."
Exploring with his hands, Remo found that the sand in a sizable rectangle had the feel and texture of coarse-grained sandpaper, and beyond a well-defined area, it became loose and granular again.
"This isn't natural," said Remo.
Then his questing fingers found the ring under a flat rock. It was literally a brass ring, except it was hand, not finger, sized.
Stepping back, Remo lifted the ring up-and up came a long, rectangular trapdoor. The trap fell back, exposing a cavity that was lined with concrete. Remo looked down.
"Looks like a secret tunnel. So much for Martians."
"I accept nothing until it is proved or disproved," Chiun said aridly.
"Let's go," Remo said, dropping into the hole.
It was a tunnel. The beaming sunlight illuminated it for a dozen yards, and then it became as dark as the jungle tunnels Remo used to infiltrate during his Vietnam days.
They advanced through the zone of light into shadow, the visual purple in their eyes compensating until they could see shadows and shapes. Ultimately the details of the tunnel resolved as clearly as if they were in gray twilight.
Odors began drifting to their sensitive nostrils.
"I smell stuff," said Remo.
"Food," said Chiun.
"Yeah. That, too. But a chemical smell, too."
"Skulking Martians," suggested Chiun.
"Not having the faintest clue what a Martian smells like, I take a pass on the argument."
"Therefore, I win," said Chiun.
The tunnel right-angled once and then again. It was taking them unerringly in the direction of the collapsed BioBubble.
After the second turn, the space opened up, and the smell of potatoes and lettuce and other familiar foodstuffs filled their noses. The familiar humming of ordinary refrigerators made the still air vibrate.
The vast, shadowy area was crammed with familiar appliances.