“No idea.”

“I confess I’d rather take the part of the bishop.”

Munoz put his head on one side, thoughtfully, without taking his eyes off the board.

“Me too. He’s in a safer position than the knight.”

“That’s what I meant, my dear.”

“Well, I wish you luck.”

“And the same to you. And the last one to leave turn out the lights.”

A long silence followed, which Julia broke, addressing Munoz.

“Since it’s our turn to play, what’s our next move? You mentioned the white queen…”

Munoz gave a desultory glance at the board. All the possible combinations had already been analysed in his mind.

“At first I thought of taking the black pawn on c6 with our pawn on d5, but that would give our opponent too much of a breathing space. So we’ll move our queen from e7 to e4. We have only to move our king next time and we have the black king in check. Our first check.”

This time it was Cesar who moved the white queen, placing her on the corresponding square, next to the king. Julia noticed that, despite his apparent calm, his fingers were trembling slightly.

“That’s it,” nodded Munoz. And the three of them looked again at the board.

“And what will ‘he’ do next?” asked Julia.

Munoz crossed his arms, without taking his eyes off the chessboard, and stood thinking. When he replied, she knew that he hadn’t been considering the move, only whether or not he should put it into words.

“He has several options,” he said vaguely. “Some are more interesting than others. And more dangerous too. From this point on, the game branches off in several directions. There are at least four possible variants. Some would involve us in a long and complex game, which might well be his intention. With others the game could be over in four or five moves.”

“Which do you think?” asked Cesar.

“I’ll reserve judgment on that for the moment. It’s Black’s turn to move now.”

He picked up the pieces, folded the board and returned it to his raincoat pocket. Julia looked at him with some curiosity.

“It’s odd, what you said a while ago. I mean about the murderer’s sense of humour. When you said that, you’d begun to understand it. Do you really find some humour in all of this?”

“You could call it humour, or irony if you prefer,” he said. “But our enemy’s taste for puns is undeniable.” He placed one hand over the piece of paper on the table. “There’s something you may not have realised. Using the symbols Q x R, the murderer links the death of your friend with the rook taken by the black queen. Menchu’s surname was Roch, wasn’t it? And that word, like ‘rook’, has its origins in the word ‘rock’.”

“The police called this morning.” Lola Belmonte gave Julia and Munoz a sour look, as if she held them directly responsible for that intrusion. “This is all…” She searched unsuccessfully for the word, turning to her husband for help.

“Most unpleasant,” said Alfonso, who then immersed himself once more in his blatant contemplation of Julia’s bosom. It was clear that, police or no police, he had only just got out of bed. The dark circles under his still puffy eyes emphasised his habitual air of dissipation.

“It was worse than that.” Lola Belmonte had at last found the word she wanted and leaned her bony form forwards in her chair. “It was ignominious. Do you know So-and-so? Anyone would think we were the criminals.”

“And we’re not,” said her husband with ironic seriousness.

“Don’t be stupid.” Lola Belmonte gave him a spiteful look. “This is a serious conversation.”

Alfonso gave a short laugh.

“It’s a waste of time. All that matters is that the painting’s disappeared and with it our money.”

“My money, Alfonso,” said Belmonte, from his wheelchair, “if you don’t mind.”

“Just a manner of speaking, Uncle.”

“Well, be more accurate in future.”

Julia stirred the contents of her cup. The coffee was cold, and she wondered if the niece had served it like that on purpose. They’d turned up unexpectedly in the latter part of the morning on the pretext of keeping the family informed of events.

“Do you think the painting will be found?” asked the old man. He’d received them dressed casually in sweater and slippers but with a friendliness that made up for the niece’s sullen scowl. He was disconsolate now. The news of the theft and of Menchu’s murder had come as a great shock to him.

“The matter is in the hands of the police,” said Julia. “I’m sure they’ll find it.”

“I understand there’s a black market for works of art. And that they could sell it abroad.”

“Yes, that’s true, but the police have photographs. I gave them several myself. It won’t be easy to get it out of the country.”

“I can’t understand how they got into your apartment. The police told me that there’s a security lock and an electronic alarm.”

“It could have been Menchu who opened the door. The chief suspect is Max, her boyfriend. There are witnesses who saw him leaving by the street door.”

“We’ve met the boyfriend,” said Lola. “He came here with her one day. A tall, good-looking young man. Too good-looking, I thought… I hope they catch him quickly and give him what he deserves. For us” – she looked at the empty space on the wall – “the loss is irreparable.”

“At least you can claim the insurance money,” said her husband, smiling at Julia. “Thanks to the forethought of this lovely young woman…” He seemed suddenly to remember, and his face grew appropriately grave. “Although, of course, that won’t bring your friend back.”

Lola Belmonte gave Julia a spiteful look.

“That would have been the last straw if, on top of everything else, they hadn’t insured it.” She stuck out a scornful lower lip. “But Senor Montegrifo says that, compared with the price it would have got at auction, the insurance money is a pittance.”

“Have you spoken to Paco Montegrifo already?” asked Julia.

“Yes. He phoned early this morning. He almost got us out of bed with the news. That’s why we were fully informed when the police got here. He’s such a gentleman.” The niece looked at her husband with ill-concealed rancour. “I always said this business got off to a bad start.”

Alfonso made a gesture of washing his hands of the matter.

“Poor Menchu’s offer was a good one,” he said. “It’s not my fault if subsequently things got complicated. Besides, Uncle has always had the final say.” He looked at Belmonte with exaggerated respect. “Isn’t that so?”

“I’m not so sure about that,” said the niece.

Belmonte looked at Julia over the top of the cup he’d just raised to his lips, and she caught in his eyes the self-contained gleam she knew well by now.

“The painting is still in my name, Lolita,” he said, after carefully drying his lips on a crumpled handkerchief. “For good or ill, stolen or not, it’s my concern.” When his eyes met Julia’s again, there was genuine sympathy in them. “As for this young lady” – he smiled encouragingly, as if it were she who was in need of cheering up – “I’m sure her part in all this has been irreproachable.” He turned to Munoz, who had not as yet opened his mouth. “Wouldn’t you agree?”

Munoz was slumped in an armchair, his legs stretched out and his fingers interlaced beneath his chin. When he heard the question, he blinked a little and put his head on one side, as if they’d interrupted him in the middle of a complicated meditation.

“Undoubtedly,” he said.

“Do you still believe that any mystery is decipherable using mathematical laws?”

“I certainly do.”

That short exchange reminded Julia of something.

“There’s no Bach today,” she said.

“After what happened to your friend and the disappearance of the painting, it’s not a day for music.” Belmonte seemed lost in thought and then he smiled enigmatically. “Anyway, silence is just as important as organised sound. Wouldn’t you agree, Senor Munoz?”