I was woken just before midnight by the insistent, painful stab of the telephone ringing. It was Luciana. She was screaming and it took me a moment to understand her. “What have you got to say now?” she sobbed. “This is what he was planning.” Eventually I grasped that she wanted me to switch on the television. Still holding the phone, I groped for the remote control. All the channels were showing the same news: a horrific fire had spread through an old people’s home on the top floor of a building. The fire had started in an antique shop on the ground floor. “The antique shop,” Luciana screamed. “He set fire to the shop below the home.” The shop window had shattered and flames had engulfed a huge tree in the street outside. The trunk had acted as a wick, the fire running up and spreading to the upper floors of the building. Some of the branches were still in flames, touching the balconies. Firemen had managed to get inside but so far they’d brought out only dead bodies: many of the residents were bedridden and had been suffocated by the smoke.

“They called from the hospital-my grandmother’s dead. I’ve got to go and identify the body because Valentina’s still a minor. But I can’t do it. I can’t!” she screamed desperately. “I can’t cope with another morgue, the corpses, the undertakers. I don’t want to see any more corpses. I can’t go through it all again.” She started crying again, a devastated sobbing that seemed for a moment as if it might turn into a howl.

“I’ll come with you,” I said. “Look, this is what we’re going to do.” I tried to sound practical and authoritative, like a parent talking to a frightened child. “There’s no hurry to identify the body, the main thing is for you to calm down. Take a pill now. Have you got some there?”

“Yes,” she said, between sobs. “I already took one, before calling you.”

“Good. Now take another one, but only one, and wait for me to arrive. Don’t do anything else. Turn off the TV and stay in bed. I’ll be there as soon as I can.”

I asked if her sister was with her and her voice fell to a whisper.

“I told her. The day I saw you, after she came out of his house. I told her everything but she didn’t believe me. I said Bruno hadn’t believed me and now he was dead. She’s just seen the fire on TV. She was with me when they called from the hospital, we watched them bringing out the bodies, but even now she doesn’t believe me. She doesn’t realise,” her voice faltered, terrified, “she doesn’t realise she’s next.”

“Don’t think about that now. Promise me you won’t think about any of it until I get there. Just try to get some sleep.”

I hung up and sat for a few seconds, eyes riveted on the screen. They’d already brought out fourteen bodies and the count was still rising. I couldn’t believe it either. It was, simply, too monstrous. On the other hand, weren’t all these bodies the perfect screen? The name of Luciana’s grandmother amongst a growing list of dead. No one would look into it as a separate case; her death would remain for ever invisible, merged with the general tragedy. This fire wouldn’t even be considered arson, but an accident, a tragic side effect of the attacks on furniture stores. Maybe the Chinese man would be made to pay, that is if he really existed and they caught him. Was Kloster capable of planning and carrying out such an atrocity? Yes, at least in his novels he was. I could almost hear his contemptuous retort: “So you want to send me to prison because of my books?”

Then I had the fatal, misguided impulse, which I have regretted every single day since-the urge to act, to intervene. I dialled Kloster’s number. He didn’t answer and there was no answering machine. I dressed quickly and hailed a taxi outside my building. We drove through the night, its silence interrupted only by the distant wail of fire engines. Over the radio in the taxi I heard news of more fires, multiplying like a virus across the city, and now and again the morbid repetition of the list of dead at the care home. The taxi dropped me outside Kloster’s house. The windows were shuttered and I could see no light through the slats. I rang the doorbell a couple of times, to no avail. Then I remembered what Luciana had once said about Kloster and his habit of swimming in the evening. I went into the café where she and I had sat two weeks earlier, and asked the waiter if there was a club nearby with a swimming pool. There was, just round the block. I hurried there. Marble steps led up to a revolving door with a brass plaque beside it. Inside I rang the bell at the reception desk and a tired-looking porter appeared. I asked for the swimming pool and he pointed to a sign showing the opening hours: it closed at midnight. I described Kloster and asked if he’d seen him. He nodded and indicated the staircase leading up to the bar and the pool tables. I went up the two flights and found myself in a large smoke-filled room. A crowd of poker players sat in silent concentration at round tables. They glanced up warily when I appeared at the top of the stairs, but soon went back to their cards. It was only then that I realised why the club was still open at midnight: it was a thinly disguised gambling den. At the bar a muted television was tuned to a sports channel. There was a ping-pong table, with the net already taken down, and, beyond it, a few pool tables. At the last one, next to a window looking on to the street, I saw Kloster, playing alone, a glass resting on the edge of the table. I walked over. His hair was swept back and still damp, as if he’d only just come out of the changing room, and his sharp features stood out in the lamplight. He was absorbed in calculating the trajectory of a ball, his chin resting on his cue, and it was only when he moved to a corner of the table and prepared to take his shot that he noticed me.

“What are you doing here? Some field work on games of chance? Or have you come for a game with the boys?”

He looked at me serenely with only mild interest as he applied chalk to the tip of his cue.

“Actually I was looking for you. I thought you’d be at the pool, but they told me you were here.”

“I always come up here after my swim. Especially since discovering this game. I rather looked down on it when I was young. I thought it a game for bar-room show-offs-you know what I mean. But it has interesting metaphors, and its own little philosophy. Have you ever tried to play it seriously?”

I shook my head.

“Essentially it’s geometry, of course. And the most classical kind: action and reaction. The kingdom of causality, you might say. Any spectator can see the obvious trajectory for a shot. That’s how beginners play: thinking only about sinking the next ball, they pick the most direct path. But as soon as you start to understand the game you realise that what really matters is controlling the trajectory of the white after impact. And that’s considerably more difficult. You have to anticipate all the possible ways the balls might strike one another, the chain reactions. Because the true object of the game, the trick, lies not in sinking the ball, but in sinking it and leaving the white free and positioned so that it can strike again. That’s why, of all possible trajectories, professionals sometimes choose the least direct, the most unexpected, because they’re always thinking one shot ahead. They want not just to strike the ball, but to strike and not stop until they’ve sunk them all. It’s geometry, yes, but of a fierce kind.” He moved to where he’d left his glass, took a sip, and looked at me, eyebrows slightly raised. “So what’s the question that was so urgent you came all the way here and couldn’t wait till morning?”

“You haven’t heard about the fire? You don’t know anything?” I scanned his face for any sign of pretence, but Kloster remained unperturbed, as if he really didn’t know what I was talking about.

“I heard there were some fires yesterday, something about furniture showrooms. But I don’t really keep up with the news,” he said.