“I suppose it’s possible, though it sounds a little complicated. It seems more like the kind of murder he’d devise for one of his novels,” I said. But at the same time, and perhaps precisely because of that, I had to admit to myself that it didn’t seem all that unreasonable. “But how could he have managed it with your boyfriend?”

Luciana looked at me, eyes shining, as if she were about to confide a magical formula that she alone in the world had discovered.

“‘The cup of coffee with milk. That was the key. I woke up with a start early one morning and it came to me: I remembered the row with Ramiro over the waitress and how my coffee-the one with milk-was always cold. I’d thought it was petty spitefulness on her part when in fact, with hindsight, I realised it was just something all waiters do: to save herself a trip she sometimes waited for another order to be put on her tray, together with ours. As she was the only one waiting on the tables outside, it also quite often happened that orders were left at the bar for a minute, until she went back inside. Kloster was sitting right there, where the owner of the bar placed the trays with the cups. And he knew very well that I always had milk in my coffee, which meant he knew that the black coffee had to be Ramiro’s. He simply waited for the first rough day, so that it would look like an accident.”

“Do you mean he poisoned your boyfriend’s coffee?”

“I don’t think it was poison; that would have been too risky. He must have known that there’d be a routine postmortem afterwards. I think he chose a substance that pathologists wouldn’t automatically be looking for, something that could cause arrhythmia, or the beginnings of suffocation, or maybe massive cramps. He was a swimmer, so he’d know, say, that a sudden potassium deficiency causes cramps. It could simply have been a powerful diuretic. At first, I didn’t realise exactly how it had all happened. I thought I’d have to convince Ramiro’s parents to have his body exhumed, but now I think that would only have made things worse. I’m sure he planned this too: nothing unusual would be detected and he’d be above suspicion once again.”