Jupe paused again, remembering.

“Go on. Don’t stop in the middle of a solo,” Bob complained. “We’re waiting for the part about Dusty and Blondie.”

“When Brit got to the lake,” Jupe went on, “he had a little white burro with him. He had found her running wild near the cave. He made friends with her and led her down to Dusty’s ranch. Then he disappeared back into the mountains alone.”

“Why?” Pete asked. “Why didn’t he just leave her where she was?”

“Because Brit was afraid Blondie would die if she stayed in the mountains. He had to get a vet for her and the nearest one was in Lareto. Ascencion did get the vet, who cured Blondie.”

“What was wrong with her?” Pete demanded. “I mean, she couldn’t have been all that sick if she made it as far as Dusty’s ranch.”

“She had a very bad eye infection.” That was one of the parts of Mercedes’ story that had most interested Jupe. It explained something that had been nagging at him for days. Why had Blondie recognized him only by his voice? Why didn’t she know Jupe didn’t look like the other young American, Brit?

“When Brit found her in the mountains,” he continued, “Blondie was blind.” Jupe remembered Ascencion’s words: She thinks you saved her life.

Pete whistled softly. “It does all begin to add up,” he said. “If Dusty knew Brit and his father had found old Pancho Villa’s silver — ”

“Yeah,” Jupe interrupted. “Mercedes says he tried to follow Brit back to it. But Brit was too fast and too smart for him. He covered his own tracks. So Dusty was left with Blondie. The only one who could lead him to the loot. But Blondie didn’t want to lead him anywhere. Not without someone whose voice she thought she recognized.”

“So Dusty had to find a voice that matched Brit’s,” Pete said. “That’s what that whole puzzle contest was about.”

“And you got the part, Jupe,” Bob put in. “But what beats me is why Mercedes told you about the cave and those silver pesos.”

“Yeah,” Pete added. “Since she tried to keep us off the bus.”

That same question had bothered Jupiter.

“She wouldn’t let me ask her any questions,” he said. “Except when I didn’t follow her Spanish. So I’m just telling you what she told me. She doesn’t trust Dusty farther than she can throw him. She doesn’t believe his horse was going lame. She thinks he’s only a few hours behind us. She’s scared he’ll kill Brit and his father when he finds them. And he’ll kill her, too, if he sees her. So she said she was going back to the lake. And she wants us to get moving. Get to the cave and warn Brit and his father that Dusty is close behind us and may show up any minute.”

There was a long silence while the Three Investigators gazed into the fire.

Pete finally spoke. “You believe her?” he asked Jupe.

“I don’t know,” Jupe admitted. “Why’s she so hot on us finding Brit and his father? Or maybe it’s the silver she wants us to find.”

“Yeah,” Bob agreed. “So she can follow us and get her hands on that dough herself.”

The next morning the three investigators were up before dawn. Over a quick breakfast they talked some more about Mercedes.

“She tried to con us at least once last night,” Jupe remembered.

“How?” Pete asked.

“When she looked at her watch and said she had to get back to the lake. She wanted us to think she was leaving right away.”

“You’re right,” Bob agreed. “Like, how far could she make it in these hills at night?”

“Something else about that watch,” Jupe went on. “It had slipped down her wrist and when she pushed it back up, I thought” — he shrugged — “I don’t know. Maybe it was just a trick of the firelight. I thought I saw a kind of scar on her wrist.”

Neither of the others had noticed that. But Bob did have something else to add about Mercedes.

“She’s one tricky lady, all right,” he said with a grin. “For one thing, there aren’t all that many Mexican women who wear contact lenses. For another thing — ”

“Contact lenses?” Pete interrupted.

“I saw her cleaning them on the bus. She kept her head down so I wouldn’t see what she was doing. But she’s got a little kit just like mine.”

“What’s the other thing?” Jupe demanded. He felt like blowing his top when Bob casually came out with delayed bits of information like that.

“The other thing” — Bob was still smiling maddeningly — “is what’s she doing wandering around the Sierra Madre with a walkie-talkie?” He finished his beans and scraped his plate clean with a handful of pine needles while Jupiter silently counted to ten. “I thought I saw an antenna sticking out of one of those packs on her burro while she was giving you that pitch about Pancho Villa. So I checked it out. I’m telling you straight, she’s got a walkie-talkie, all right.”

“Who’s she hoping to walkie-talk to way up here?” Pete wondered. “It can’t be Dusty. I’ve helped him pack and unpack that dumb horse so many times, I can swear he hasn’t got one.”

“Ascencion does,” Jupe remembered. “I helped him fix it. But there’s no way any walkie-talkie in the world could transmit from here all the way back to the ranch.”

They stood up and carefully stamped out the fire. Then they packed up their gear and Jupe roped it onto Blondie’s shoulders.

“What if,” Jupe said thoughtfully, stroking the little burro’s neck, “what if Mercedes isn’t going back to the lake. What if she’s hiding out among the rocks right now.” He looked around him in the gathering light. “Waiting for us to move on so she can follow our tracks. But she doesn’t want us to catch on to the fact that she’s after those pesos too.”

Pete shrugged. “If that’s what she wants, she’s got us. There’s no way we can hide all our tracks.”

“True.” Jupe started to lead the burro out of the clearing. “But we do have one advantage.”

“What?”

“Blondie made friends with Mercedes’ burro last night. And from what Hector Sebastian told me, once burros know each other, they can sense one another a long way off. And they’ll bray to each other. So if Mercedes and her burro come within a couple of miles of us, Blondie will let us know it.”

That day’s journey was the hardest of all. Blondie had started climbing the tallest and steepest mountain they had seen. The little burro had to keep zigzagging along deep gullies as she moved slowly up toward the distant peak.

She never stopped or brayed. And though the Three Investigators kept glancing back, they never caught sight of Mercedes or her burro.

They did see another thick plume of smoke. It seemed to rise from around the flattened top of the mountain they were climbing.

“Weirdest forest fire I ever saw,” Pete said. “Where’s the forest? Not a thing up there except a few cactus.”

“You’re right,” Jupe agreed. “But the smoke could be coming from the other side of the mountain. If the fire circles below us, we’re going to get cut off.”

“Great,” Bob said. “Not only do we have a psychopathic liar and a shifty woman following us, but now we’ve got a forest fire to contend with too.”

Pete was watching the sky. “Weirdest smoke I ever saw, too,” he went on. “It goes up. But it doesn’t stay there. It just disappears.”

Bob looked up as flights of birds passed high overhead. Hawks and kites and vultures. “Lucky bums,” he said. “Hightailing it out of here before they get cooked.”

They pushed on. Jupe’s eagerness to solve the riddle and his slimmer girth made it easy for him to bound up the trail after Blondie. By early afternoon he and the burro were well ahead of Pete and Bob.

Then the two guys suddenly heard Jupe’s voice echoing down the mountainside.

“Stop,” he yelled to them. “Stay where you are.”

They both stopped at once. Looking up, they saw Jupe raise his hands above his head.

“Now come closer,” they heard him call. “Just follow the burro slowly.”