Vargas paused and Torres cut in again. “It feels like we are up against a secret army that is always one step ahead of us.”

“And that, Juan, is possibly the most worrying aspect of this entire case.”

Vargas moved towards his office and signalled for Torres to join him.

As they walked together, Vargas suddenly stopped dead in his tracks. At the opposite side of the open-plan office, two senior detectives were deep in conversation with a female, also dressed in civilian clothes. She had her back to Vargas, but, for a brief moment, he believed for all the world that he was looking at his wife. Her particular stance, her petite frame and her long black hair were so much like Sophia, Vargas was convinced it was her and was transfixed. Torres followed his superior’s eyeline and smiled.

“She’s a hot one, chief, but I’ve heard she is a bit of a ball-breaker. She’s the deputy head of HR and works out of the commander’s office.”

Torres’s voice brought Vargas back to earth but his hands trembled as he wiped his brow and he swallowed hard. Slowly he gathered himself together and led Torres into his office. Once the two detectives were alone, Vargas finally managed to pick up the thread of his thoughts.

“Juan, I think they must have someone on the inside. It’s uncanny how they always seem to be one step ahead of us. From now on, any major operational decisions need to be kept between you and me until the very last possible moment. We don’t know who we can trust.”

“Understood, chief. By the way, what you said out there about a hitman, do you really believe that?”

“Yep. And, as I said, I think he is probably long gone and—”

Vargas was interrupted by Detective Martin, who knocked and opened the office door in one simultaneous movement. He strode in, accompanied by another man who neither Vargas nor Torres recognised. He was casually dressed in a black T-shirt and a pair of washed-out Levi’s.

“I’m sorry to crash in, sir. This is Daniel Colombo from IT. He’s been working on the mobile that you found at Ramos’s flat.”

Vargas smiled at the young tech expert and gestured for him to take the chair in front of his desk. “Daniel, we could really do with some good news. What have you got for us?”

Colombo placed the iPhone down on Vargas’s desk. “Chief inspector, the data on this phone has been encoded and encrypted to a level that I’ve never seen before. Plus, everything has a triple-lock password, which makes it almost impenetrable.”

“Daniel, what do you mean by almost?”

“Well, we did get a small break, sir. For some reason, the very last call made by this mobile didn’t get fully encrypted.”

Vargas almost leapt out of his chair. “So we have a lead?”