Roberto read silently.

—“Sixty-year cycles… pressure anomalies…” he murmured. “Mom, are there more letters?”

—Yes. There’s one for every situation. Even one in case they tried to kick me off the ranch.

Roberto looked up.

—Kick you out?

—Or convince me to sell.

That night he saw a car stopped on the country road, lights off, two men looking toward the ranch. When we turned on the porch light, they sped off

“You were right,” Roberto said. “Something strange is going on here. And it’s not just the weather.”

From then on, we worked together. Roberto was strong and methodical. The wall grew quickly: stone, cement, perfect drainage. Meanwhile, he investigated “Inversiones Sierra SA de CV,” the company Beatriz mentioned so often.

One afternoon Beatriz returned, this time with a man carrying a briefcase.

—Margarita, this is Dr. Álvarez. Psychiatrist. He’s come to talk to you.

Roberto came out of the shed, his hands dirty with mortar.

—Hello, Aunt Beatriz. What’s a psychiatrist doing at my mother’s house without an invitation?

Beatriz paled.

“Roberto… I didn’t know you were here. I thought…”

“My mother is perfectly fine,” Roberto said coldly. “In fact, we’re working together. And I have a question for you. Who is ‘Inversiones Sierra SA de CV’?”

Beatriz stepped back.

“I don’t know what you’re talking about.”

“Yes, you do. It’s the company that wants to buy the ranch for next to nothing. And you’re acting as the intermediary.”

“That’s a lie!” she shouted. “I’m doing it for her own good! She’s crazy! She’s going to spend her savings on that ridiculous wall!”

—Get out of my house—I ordered, advancing—. Out with you and your doctor.

The psychiatrist tried to mediate. Roberto cut him off.

—Get out.

When they left, Roberto looked at me

—Mom, I’ve been looking into historical data. The winter of 1965 was brutal. Houses collapsed, livestock died. And it happened exactly sixty years after the great snowstorm of 1905.

—The cycle—I whispered.

—Yes. Dad was right. There’s a pattern. And if the calculations are correct… we have two weeks left

We worked like mad. The large steel gates arrived from Cuauhtémoc’s blacksmith shop. The wall was almost completely enclosed.

Daniel, the young meteorologist who took Guillermo’s place, came running one morning.

—Doña Marga… the barometers have gone crazy. The pressure has plummeted. A monstrous polar air mass is coming. In 48 hours…