St Paul’s Labyrinth. Jeroen Windmeijer

walk part of the way back together.

      Now, just before six, he was sitting in a shop doorway.

      He had washed his hands in the toilets of a nearby pub, but no matter how much he’d scrubbed, he hadn’t been able to get rid of the blood that had found its way under his fingernails. His shirt and jacket were covered in dust.

      He sat in a daze, holding the phone that had been left in the lecture theatre, half-expecting a new message to arrive. But it stayed silent.

      He opened Google. He noticed that the internet connection was fast now. He typed in ‘Wickr’ as a search term and learned that it was a mobile phone app similar to Snapchat. Wickr encrypted text messages and then deleted them when they had been read. The sender could decide how long messages would be stored for before they disappeared. The site security.nl said:

      Wickr is based on 256-bit symmetric AES encryption, RSA 4096 encryption, and our proprietary algorithm. ‘It is the first end-to-end encryption that does not require a PGP key,’ according to professor and co-founder Robert Statica. According to Statica, Wickr’s servers do not see user accounts. Nothing is stored except the cryptographic version of the Wickr ID and the user’s hardware ID.

      Peter read the text without understanding much of it, but it told him that the person who was sending him the messages wanted to remain anonymous.

      He took a silver case from his other inside pocket and flipped it open. Inside was a single cigarillo, held in place with a small clip. Every Sunday, he refilled the case with exactly five little cigars. In the old days, he’d smoked in his room at the faculty, but the university’s smoking ban had put an end to that. Sometimes he wistfully remembered the days when he could just light a cigar and watch the smoke curl upwards as he collected his thoughts.

      He lit his last cigarillo of the week, took his earphones from his pocket and put them in his ears. Then, on his own phone, he opened a Spotify playlist that he had filled with the works of Bach. He’d become something of an expert on Bach’s cantatas over the years. They had a meditative effect on him. He had once spent some time looking into the numerological symbolism in Bach’s compositions, but had soon found himself out of his depth.

      ‘Erfreut euch, ihr Herzen, entweichet, ihr Schmerzen,’ the singer lilted softly, ‘es lebet der Heiland und herrschet in euch.’ Listening to Bach was good for his German too. Rejoice, O hearts, begone O agonies, the saviour lives and reigns in you.

      After he lit his cigar, he tried to keep the spindly cedarwood spill burning for as long as he could. When the flame licked at the top of his index finger, he quickly dropped it on the ground.

      From where he sat, it looked like Janna, Daniël and Arnold were having a heated discussion about something. At one point, Arnold turned angrily away from the others and disappeared into the bar. Peter assumed he had gone to get another drink.

      But he came back outside not long afterwards, clumsily fastening his belt as he headed straight for Peter, with Daniël and Janna behind him.

      ‘Come on,’ he said with surprising articulacy, ‘we’re all going to have a look down that hole. I just want to—’

      ‘Absolutely not,’ Janna cut him off.

      Daniël wobbled his head, as Indians do when they are reluctant to say either yes or no.

      ‘I want to be the first person to walk through part of the tunnel,’ Arnold said, smiling at Janna. ‘Further than you went. Come on, let this old fogey have a bit of fun.’

      ‘It can’t hurt to have a quick look, can it?’ Daniël said, although he didn’t sound sure.

      Peter turned off his music and stood up. Speaking of networking, he thought, watching Daniël.

      Janna’s jaws were tightly clamped together. It was clear that she also understood that it would be unwise to cross the great Van Tiegem. He was known for his vindictive character.

      ‘Okay then,’ she said, like a parent giving in to a spoiled child but trying to sound strict at the same time, ‘but just a few minutes, and no more than twenty or thirty metres … I’m not taking any responsibility for this. Daniël and I will wait for you both up here so that …’

      Arnold was already tugging at the safety barriers that had been laid over the pit. He yanked at one of them with his full weight until it suddenly moved and he fell backwards. A monstrous screech of metal on stone echoed through the narrow street.

      Janna swore under her breath.

      Daniël and Peter carefully lifted the barriers up and moved them out of the way.

      ‘Is this really a good idea?’ Peter tried again.

      ‘We can hardly let him go down there on his own,’ Daniël said, with more reluctance than he had shown just moments ago. ‘And you know what he can be like once he’s got an idea in his head … I don’t want to be the one to antagonise him. But I don’t want to upset Janna either, so if you could go with him …’

      ‘Oh, great. That’s all I need,’ Peter mumbled like a sulky child.

      Janna, who had apparently decided to make the best of a bad situation by at least making sure everything was done correctly, fetched the rope ladder and secured the two pegs firmly in the ground. She produced two bulky hardhats with lamps on them from an enormous bag and gave them to Peter and Arnold.

      ‘You can use the light on your phone as well if you need to,’ she said.

      Arnold was already crawling over to the ladder on his hands and knees.

      ‘Those who are about to descend salute you,’ he said, tapping his helmet in a jocular salute.

      A fiery bolt of annoyance shot through Peter.

      Daniël helped Arnold by guiding his feet onto the first rung of the ladder. The ladder wobbled as he steadied himself, but he quickly found his balance.

      If this was the circus, the audience would be applauding with relief now, Peter thought.

      When Arnold reached the bottom, Peter got onto his knees, with his back to the pit. He felt around with his foot for the first rung. When he was sure it was secure, he lowered his other foot and began to climb down.

      ‘You brought me up from the grave, O Lord. You kept me from falling into the pit of death,’ he murmured.

      He glanced into the gaping black chasm below him now and then as he descended and saw the faint glow of light from Arnold’s hardhat. When he reached the hole at the bottom of the pit, he lay on his front, dangled his legs over the edge and slowly slid down into the darkness.

      ‘You’ve got to see this,’ he heard Arnold say in the distance, as though he was talking to no one in particular. He said it again, and this time there was a note of bewilderment in his voice. ‘You’ve got to see this!’

      The lamp on Peter’s helmet gave off a bright, broad beam of light, but it only made the gloom beyond it seem even blacker.

      Arnold had walked in the direction of the Hooglandse Kerk and then stopped, a few metres away from Peter.

      ‘What, exactly, have I got to see?’ Peter asked. But as soon as he got closer, he saw what Arnold meant. Fixed to the wall at shoulder height was a metal ring that held a blackened torch.

      Arnold touched it hesitantly, as though he expected it to burn his hand. He looked at his sooty fingers and rubbed them together.

      ‘That’s what my hands look like when I clean out the grate after we’ve been burning logs all evening. This torch has only just been put out.’

      ‘What is this?’ Peter said, astonished by how calmly Arnold was handling this absurd situation, as though he had been through much worse before.

      Suddenly, they heard something fall not far from where they were standing. Arnold turned around so abruptly that his hardhat fell off. He clumsily tried to catch it, but