“Alex, can you bring me the list showing the owners of the boxes that were actually stolen in the raid?”

Two minutes later, Detective Alex Martin entered Vargas’s office and handed over a single piece of paper listing the details of ninety safe-deposit boxes.

Vargas had read it before, but this time he scrutinised it, looking for one particular name. “Jesus fucking Christ!” He leapt out of his chair, ran around his desk and grabbed the young detective in a crushing bear hug. “Alex, we have a match. One of the stolen boxes is owned by the Franklin Pharmaceutical Corporation. This whole fucking case has been about Box 1321.”

Vargas summoned Torres and brought him up to speed while he placed a call to the manager of the Banco Estero. Within a few seconds, the bank switchboard operator had Marcelo Morales on the line.

“Señor Morales, I want you to tell me everything you know about Box 1321.”

Morales was slightly taken aback by the bluntness of the request. “Chief inspector, you have to understand that—”

He was cut short by Vargas. “Let me explain something to you, Señor Morales. Nine people have been brutally murdered in the last two weeks, including one of my men. And they’ve all died as a direct result of whatever is inside that box. So, let me ask you again, what do you know about Box 1321?”

Morales felt the sheer wrath coming his way and changed his tone. “Chief inspector, please give me a few moments to find the paperwork.”

Vargas tried his best to stay calm while he waited for the manager of the bank to come back on the line. It was nearly five minutes before Morales returned. He sat back at his desk and opened a thin grey folder.

“The box was first rented on 7 July 1981. It was taken out by the Franklin Pharmaceutical Corporation and is registered to their head office in Buenos Aires.”

Vargas jumped in with a question and held his breath as he awaited the reply. “Can you give me the names and exact dates of every person who has ever visited the bank to check on the box?”

“That’s the strange thing about Box 1321. It hasn’t been visited since the day it was opened thirty-one years ago.”

Vargas shook his head in disbelief as he ended the call and glanced down at the American phone number. “The mystery surrounding this box gets weirder by the minute. Let’s see where this takes us.”