“Make sure it’s enough to cover any kindergartners he might eat.”

“Sam!” said Remi.

“We’ll call before we get on the plane.”

Sam used Remi’s computer to buy plane tickets home. Then he researched the names of American archaeology professors specializing in the Mayans. It was a pleasant surprise that one of the most distinguished seemed to be Professor David Caine at the University of California at San Diego. Sam e-mailed Dr. Caine and said that he and Remi had made an unusual find at Volcán Tacaná, and attached the Mexican news article about it. He asked Caine if he would meet with them when they returned home. He asked Remi to read the e-mail before he sent it.

She did, and said, “My advice is, click send.”

“You don’t think we ought to include something about ourselves? Maybe list the places we’ve excavated in other countries and so on?”

“Nobody needs to do that anymore. When he reads this, he’ll be sitting in front of a computer. He can Google us and get much more than he wants to know.”

“I suppose.”

Within an hour, Professor Caine answered. He said he would be happy to meet with them and was eager to learn more about their latest find. Remi pointed at the screen. “See that? Our ‘latest find.’ He Googled us first thing.”

That afternoon, Sam and Remi checked out of the hotel and hired a taxi for the ride to the airport south of the city. The driver put their two backpacks into the trunk. As she was about to get into the cab, Remi hesitated for a second.

“What?” Sam said. “Something wrong?”

She shook her head. “Just a guy waiting outside the main entrance. When we came out, he ran.”

“Where to?”

“I don’t know. Down the street, I guess.”

“Could he be a parking attendant going to retrieve somebody else’s car?”

“Sure. That’s probably it,” she said. “I guess I’m a little jumpy today. Some of the experiences we’ve had lately . . .”

They got into the backseat, and the driver said in English, “Which airline?”

“Aeromexico.”

The cab dove off down the long driveway toward the federal highway. The airport was about ten miles away and the traffic was moving steadily, so they made good time. They looked out at the Gulf of Mexico and enjoyed the ride.

Just as they could see the airport ahead to their right, a black car came speeding up behind them. It pulled up beside them, and a stern-faced man in a dark suit gestured to them to pull over.