“Well, sir, just after midday, we took a call from a woman named Elena Sanchez. She is a council carer who works in the La Boca district. Apparently, one of the other carers didn’t turn up for work this morning and hadn’t called in sick either, which is highly unusual. Sanchez was sent out to take over the rest of the daily visits and her first one was here. When she arrived, she found the front door open and no sign of Gonzales. She checked the entire house but it was empty, although his wheelchair was in the sitting room. The upstairs bedroom was a total mess, stuff thrown about everywhere. She was about to leave when she spotted the back door open, which led her to check out the shed.”

“Where is she now?”

“After we took her statement, one of our cars took her home. I told her we would probably want to interview her again down the line.”

Vargas tuned to the pathologist, Dr Hugo Fernández, who was busy taking photographs of the body. “What can you tell us, doctor?”

“It’s early days but I can give you some headlines. Señor Gonzales, if that’s who this is, was killed some time in the last few hours by a single gunshot to the head. Looking at the burns on the skin, I would say the gun was held very close to the forehead. There’s an exit wound at the back of the skull, so the bullet may well be embedded in one of the concrete walls. There’s no obvious signs of resistance on the body, so this feels like a cold-blooded execution.”

Vargas turned back to Vega. “Officer, I want you to find that bullet. Don’t touch anything else until the lab boys have given the shed a full dusting. Clearly, we will need to bag up all this stuff very carefully before taking it away.” Vargas turned towards the door. “Juan, let’s take a look inside.”

Vargas and Torres toured the house before ending up in the small sitting room which, unlike the upstairs bedroom, appeared neat and tidy. The only things that seemed slightly off were the TV plug and lead lying in the middle of the floor next to the empty wheelchair and the upturned cereal bowl.

“So whoever did this was clearly looking for the deposit-box haul in the house and then discovered it was in the shed. But what does an old man like Gonzales have to do with the robbery? He was an invalid, for Christ’s sake—”

Torres interrupted his boss. “Even more puzzling is why did they shoot him and leave millions of dollars behind?”

Vargas wasn’t listening to his colleague. His attention had turned to a small framed family photograph sitting on the windowsill. He picked up the wooden frame and showed it to Torres. “What do you see here, Juan?”