Capital

already at their desks by seven. If you wanted to be on your own in the building, you had to get there well before six.
    At half past five, when Mark came into the foyer, the night guards were still on duty. He had got home from the charity dinner at quarter to one, and slept for four hours; it was a sign of his strength of will that he had been able to train himself to not need much sleep. In the dark, the atrium looked warm and inviting, much more so than it did in daylight, when the vast expanses of glass made it seem overheated and airless. Today the security desk was occupied by an unspeaking, unsmiling Caribbean man in his fifties. He checked Mark’s ID and signed him in. Mark went through into the lift. He looked at his reflection in the stainless steel. He said:
    ‘I’ve come in to get a jump on the weekly figures, before the meeting with Lothar.’ His voice, bouncing back off the metal walls, sounded sincere. It was good to practise; this was something he always did, when he had a lie he knew he was likely to have to tell: say it out loud, to check how it sounded. ‘Got to get ready for the meeting,’ he said. ‘It’s like they say in the SAS. The seven Ps: Proper Planning and Preparation Prevent Piss-Poor Performance.’
    He was fine. There would in all probability be no one in before six o’clock or so. Certainly no one was in yet; he had checked the out-of-hours sign-in sheet when he came through security.
    Mark liked being on his own in the trading room. There was something creepy about the empty space, the blank monitors and the dark outside, the uncanny stillness in a room designed for a crowd, for noise, for shouting and anxiety and action and looking at three screens while talking on two phones while juggling a dozen trades; but that unsettlingness was what he liked about it. Most people could not do this. They would be too freaked out. But he was not most people. That was the whole point.
    He dropped his briefcase at his desk, took his jacket off, and stretched. Today’s mission was passwords. About a year before, Pinker Lloyd had called in a team of outside consultants to assess its levels of risk in relation to computer fraud and hacking attacks. One of the main recommendations had been that the bank was too lax in the security level of its passwords, in particular because it allowed employees to set their own. In too many cases people used passwords that they used on other computers; in some of the most egregious cases, people even had the same password on all their accounts, for work and home. This was flagrantly unsafe: any third party getting hold of someone’s private email password, or eBay account password, or any password set up on any internet shopping site, would have access straight into Pinker Lloyd’s systems. Not acceptable. So the recommendation was for the company to adopt new protocols for anything that allowed access to its systems, unguessable chains of letters and numbers with rAnd0m caPItalisåtiºn. The new passwords would change weekly. The logic was impeccable. But it was also mistaken, because the new passwords had a flaw: they might be unguessable, but they were also unmemorisable. Since no one could keep the passwords in their heads, everybody wrote them down. So all you had to do to get access to someone’s account was to find where they had written down their password.
    Mark first went into Roger’s office. His undeserved corner office, with the view of Canary Wharf and the river, the family photos on the desk; the office which was going to be his. He woke Roger’s computer up from sleep, then navigated to the file called ‘Passwords’. If he had to sum up his boss’s stupidity in one detail, it would be the fact that he hid his passwords in a file marked ‘Passwords’. The file was itself protected by a password, but Mark had seen Roger type the first few letters of it, and because Mark was not an ordinary man, with only a little thought he had been able to deduce the rest. The first letters typed were c o n so it had been easy to work out that the password was conradjoshua, his horrible children’s names run together. He opened the file to see Roger’s bank passwords. They were the usual strings of letters and numbers. Mark took a note of them in his little Moleskine book.
    He went back on the trading floor. He began with the passwords whose hiding places he knew: on a piece of paper; in a locked drawer, whose key was in turn left in a jar of