Erika looked over at the Pavilion Theatre, which loomed up like a giant curved jelly mould, the pier stretching out to sea behind it. A large flock of seagulls huddled together on the end, their heads buried in their feathers.

‘What if we can engineer a meeting between Keith and “Night Owl”?’ said Erika.

‘Where? And how would we get him there? And if she saw him, wouldn’t she just turn around and…’

‘No, Peterson. Keith wouldn’t be waiting for her. We would. Along with half the Met Police.’

71

Later that day, Erika had managed to call in a favour from Lee Graham, an old colleague from the Met who was now with Sussex Police. He came over to Worthing to look at Keith’s computer. He was a brilliant, young and slightly intense forensic computer analyst.

A couple of hours later, Lee, Erika, Peterson and Keith were all crammed into Keith’s tiny living room.

‘Okay, so you’ve now got his computer—’ started Lee.

‘My name is Keith,’ said Keith, regarding Lee suspiciously.

‘Yes, you’ve now got Keith’s computer here networked in with these,’ said Lee, handing two laptops to Erika. ‘You’ll be able to see what’s happening in real time and you can also jump in at any time and type. Whoever is chatting with Keith online won’t be any the wiser.’

‘Thank you,’ said Erika.

‘I can also keep a log and I’ll be able to monitor the chat room remotely from my office. I’ll have a crack at tracing this Night Owl’s whereabouts, but if she’s using the Tor network it’ll be virtually impossible.’

‘So, how does this Tor network operate?’ asked Peterson.

‘Say you use the Internet normally, for example to send me an email. It goes from your computer via a server to my computer. Both of us can easily find out where the other person is via their IP address. An IP address is a unique string of numbers separated by full stops that identifies each computer using the Internet Protocol to communicate over a network. With the Tor software on your computer, it directs Internet traffic through a free, worldwide volunteer network of computers. There are more than seven thousand of these acting as relays to conceal a user's location and usage from anyone conducting network surveillance or traffic analysis.’

‘They call it onion computing, because there are so many layers in the relay,’ said Keith.

‘That’s right. Using Tor makes it more difficult for Internet activity to be traced back to the user. This includes visits to websites, online posts, instant messages and other forms of communication,’ said Lee.

‘And anyone can download this Tor program?’ asked Erika.

‘Yep. Free online software,’ said Lee. ‘Makes it a bloody nightmare for us.’

‘If you can’t trace Night Owl, then why do you want to spy on me talking to her?’ asked Keith.

A look passed between Erika and Peterson.

‘We want you to arrange a meeting with her,’ said Erika.

‘I can’t meet her. I’m not ready. I wanted to be able to prepare!’

‘You’re not really going to meet her,’ explained Erika.

‘No, no, I can’t… I’m sorry. No.’

‘You will,’ said Peterson, with an air of finality.

‘London Waterloo train station,’ said Erika.

‘How am I going to suddenly think of a way to get her to meet?’ cried Keith, panicking.

‘You’ll think of a way,’ said Peterson.

‘I saw that you’ve saved your entire chat room history with this Night Owl,’ said Lee. ‘I’ve copied it across to your laptops,’ he told Erika and Peterson.

‘But… those were private chats!’ insisted Keith.

‘We have a deal here. Remember?’ said Erika.

Keith nodded, nervously.

When everything was set up, Erika and Peterson came out of the flat to say goodbye to Lee. The air was still and warm, and from far down on the beach they could hear the squeaky strains of a Punch and Judy show.

‘I also got a copy of his hard drive. I’ll check out if there’s anything dodgy we need to know about,’ said Lee, going to his car, which was parked by the kerb. He opened the boot and put his bag inside. ‘I sometimes wish that the Internet had never been invented. Too many people with too much time to indulge their sick fantasies.’

‘It seems every time I see you I’m giving you something nasty to look into,’ said Erika. ‘Thanks for doing this.’