'Did you hear about Carla? She died last night.'

'I know.' Cadel had been plugged into the electronic grapevine. 'Poison.'

'Really? Poison? Wow,' said Gazo, his eyes widening behind his mask. 'What kind of poison?'

'Look a uh a I think you'd better go,' Cadel advised. 'Before Dr Vee gets back.'

'Oh. Right.'

'We can talk later,' said Cadel, ignoring Gazo's obvious disappointment.

'Sure. No problem.' Gazo nodded, and began to back out of the room. 'Enjoy the sandwich!' he said, before disappearing.

Cadel didn't enjoy the sandwich. He didn't even sample it; he had gone right off inst.i.tute food. The Axis mailboxes were now full of reports on Carla's condition, which had finally been diagnosed: she had been poisoned with a fatal dose of thallium. Nothing could have been done to save her, since the effects of the poison couldn't be reversed once it had been in the stomach for more than half an hour. Gloomily, Cadel read through the emails that Luther Lasco was dispatching in all directions. The thallium, Luther a.s.sured Thaddeus, had not come from his own stash. Like the rest of his poison supply, his own stock of thallium was completely secure. Had Carla read the early intervention training material distributed to every staff member, she would have known that symptoms like vomiting, diarrhoea and joint pain often meant more than a tummy bug. By the time she'd started to lose feeling in her toes and fingers, it had been too late.

I can't stress enough, Luther wrote to Terry, the importance of early intervention in poisoning cases. At the Axis Inst.i.tute, there is no such thing as a harmless tummy bug. Thallium, he added, was tasteless and colourless, and in this case had probably been administered in the labs, since Carla had been at work for more than three hours before being whisked away in the ambulance.

Luther advised Terry to have the labs thoroughly searched once again. Anything edible was to be removed and destroyed. The taps in the bathrooms had to be tested. Meanwhile, he said, he was working the source for further information.

Cadel wondered who, or what, this mysterious 'source' might be. Just before leaving the inst.i.tute, he found out. One last sweep through the network uncovered an encrypted message sent to Terry from Thaddeus. Cadel decoded it easily, to discover that Thaddeus wanted Terry's urgent a.s.sistance in disguising Carla's death as something 'trouble-free'. They had identified the culprit a Doris Deauville. They had identified the agent a thallium. Was there any way in which Carla's rapid decline could somehow be blamed on natural causes? Or would they have to resort to more drastic action? They couldn't afford to have the coroner order an autopsy, so the corpse might have to be disposed of.

Doris Deauville, thought Cadel, swallowing hard. He wasn't surprised. Though he did wonder why Doris, the expert poisoner, had used a poison that left traces of itself in the victim's body. Surely there were other, undetectable poisons? He remembered the twins talking about a certain substance a insulin, was it? Or something else?

Maybe Doris had simply lost her temper and used the first thing that came to hand. Whatever the reason, Cadel preferred not to think about it. He was far more concerned about Kay-Lee. On his way from the inst.i.tute to Thaddeus's office, he decided that if he hadn't heard from Kay-Lee by eight o'clock that evening, he would call Weatherwood House. Just to make sure that she was all right. He didn't have to reveal who he really was. He could pretend to be collecting for a charity, or something.

When Cadel arrived for his appointment with Thaddeus, Wilfreda informed him 'that the doctor had been delayed'. She bared her blackened teeth at him and suggested that he wait in the upstairs office. Then she asked Cadel if he would like something to eat. A biscuit, perhaps? A drink?

'Yes, please,' he replied. Wilfreda kept one jar of chocolate biscuits under her desk, doling out the contents when she was in a good mood.

Cadel took two biscuits and a gla.s.s of water before trudging up to the top floor. Nothing had changed on the staircase since his first visit. The same mottled engravings hung on the wall. The same shabby runner was pinned down by the same tarnished bra.s.s stair rods. The bathroom off the first landing had not been touched, save for the occasional scrub-down and change of toilet paper. It remained gloomy and old-fashioned, with its wooden toilet seat, dangling chain and cream tiles.

But Thaddeus's room had changed. Thaddeus had installed two brand new micro-suede couches the previous week, and hung new curtains at the windows. The carpet was now about three years old. And the technology, of course, was state-ofthe-art.

Cadel sat down in front of the psychologist's computer. Munching on a biscuit, he checked his own email a and almost choked.

A message from Kay-Lee!

Weak with relief, he opened the file. There it was.

Get stuffed, it said. This conversation is officially terminated.

Cadel caught his breath. He couldn't believe his eyes. Get stuffed? What was that supposed to mean? What are you talking about? he wrote. What's the matter? Then he thought: why am I doing this? And he picked up the phone.

He had memorised the Weatherwood House number. It rang three times before a woman's voice cut in, telling him that he had reached Weatherwood House and how could she help? He asked to speak to Kay-Lee McDougall.

'One moment, please,' the voice trilled. There was a click, and 'Greensleeves' began to play. After about two minutes, Cadel heard another click, followed by heavy breathing.

'h.e.l.lo?' somebody panted. 'This is Kay-Lee.'

Cadel was suddenly speechless.

'h.e.l.lo. h.e.l.lo?'

'Kay-Lee,' Cadel finally croaked.

'Speaking.' She was beginning to sound impatient. Her voice was unexpectedly rough a she drawled her vowels.

'Kay-Lee, it's ait's...' For a moment, his mind went blank. 'I'm a friend of Eiran's,' he gasped, knowing that the pitch and rhythm of his own voice were a dead giveaway. He quite obviously wasn't a thirty-four-year-old alcoholic Canadian.

There was a long pause.

'Oh.'

'Eiran wants to know what that message was all about,'Cadel continued. 'Why you sent it.'

'Look a'

'He wants to know if you're all right. If something's wrong a'

'Look, forget it,' said Kay-Lee. She sounded tired, and not particularly upset. 'Just forget it, okay? Lay off.'

'But a'

'Not interested. Okay? Sorry, but you've caused enough trouble.'

Clunk. She hung up.

For an instant, Cadel found it hard to breathe. That broken connection was like a punch in the belly. He thought he was going to be sick. It didn't make sense. It couldn't be true.

He was still sitting, motionless, at Thaddeus's desk when the psychologist walked in.

'Ah! Cadel. I'm very sorry, it's inexcusable to be so late, but I couldn't help it. Emergency at the inst.i.tute. Well . . .'Thaddeus gave a short laugh. 'I don't have to tell you, of all people. It was Doris, of course. We had our suspicions right from the start. Hmm.' He had picked up some unopened mail from his desktop, and was flipping through it. 'How on earth do these people track me down?' he remarked, tossing a letter into his rubbish bin. 'Do you know I've dodged some of the world's leading intelligence agencies? But when it comes to charitable organisations and insurance companies a well, they always find me in the end.'He looked up, and his gaze became intent as it focused on Cadel. 'What's wrong with you?' he asked.

'What?' said Cadel stupidly.

'Are you feeling sick?'

'Uh a no.'

'You're very pale.'

'Am I?' Cadel glanced around vaguely, as if expecting a mirror to materialise. He knew that he was suffering from a mild case of shock. 'I a I guess I didn't eat much, today.' 'Ah.' Thaddeus nodded. 'Stuck at your computer again, I suppose.'

'Something like that.'

'I'll send Wilfreda out to get you a bite.' Because there was no intercom connecting the upper and lower floors of the house, Thaddeus strolled onto the landing to summon his secretary. He called to Cadel: 'What do you want? Something hot? Fish and chips?'

Cadel couldn't think. He mentioned the first thing that popped into his head.

'Sausage roll?'

'Not very nutritious, Cadel.'

'Pizza, then. Vegetarian.'

As Thaddeus and Wilfreda discussed which company she should call, and how they would pay for the delivery, Cadel erased Kay-Lee's message from Thaddeus's computer. Although Thaddeus knew about Kay-Lee, he had never much approved of her. Cadel didn't want him to find out what she had done. It would be unbearable if Thaddeus turned around and said: 'I told you so.'

Cadel himself still couldn't believe what had happened.

'Your father wants to talk to you,' Thaddeus announced when he re-entered his office. 'He has something important to say. I'm not sure what it is, but he was very insistent. We'll have a transmission download in exactly' a he checked his watch a 'two minutes and thirty seconds. I've got it all set up, as you can see.'

'Do you think...?' Cadel hesitated, before plucking up his courage. 'I mean, it can't wait, can it? Till next time?'

Thaddeus raised his eyebrows. He hardly needed to say 'no', because Cadel immediately backed down.

'No, of course it can't wait,'he said. 'Sorry. Not thinking. But can I go to the toilet first?'

Thaddeus nodded, studying Cadel intently. Avoiding his gaze, Cadel hurried out the door and down the stairs. He shut himself in the bathroom. His stomach was churning, and he was afraid that he might be sick a or worse. But nothing happened.

Nerves, he decided. It must be nerves.

Mrs Piggott often talked about her nerves. They caused her all sorts of problems, like headaches and stomach upsets. For the first time ever, Cadel found himself sympathising with her.

Finally he washed his face and marched heavily back upstairs.

'Here he is,' said Thaddeus, who was stationed in front of his most recent transmitter screen, which was larger and more advanced. Though Dr Darkkon's transmitter was now concealed under a fake corn on his foot (a corn that he had to peel off when he wanted to speak to Cadel), advances in nanotechnology meant that Cadel saw more of his father than ever before: hands, shoulders, neck, even bits of his pudgy waist. Sometimes Cadel wondered if this was really an improvement.

'Cadel,' said Dr Darkkon, craning forward so that his bloodshot eyes became huge. 'What happened to your face?'

Cadel opened his mouth. 'Uh,'he began, realising that he hadn't thought up a good excuse. Fortunately, however, Thaddeus jumped in to save him.

'I'm afraid that's the result of faulty evacuation procedures,' he said. 'Cadel got pushed against a doorframe during a bomb scare.'

'But a'

'I've got Luther on the case now, revising guidelines,'Thaddeus a.s.sured Dr Darkkon, who frowned.

'I should hope so,'he said. 'Are you all right, son?'

'Yes,'Cadel replied.

'Sure it wasn't someone seizing the moment? Taking advantage?'

'No.'

'Well.. . as long as you're on the mend.' Dr Darkkon eyed Cadel's injuries for a moment, before taking a deep breath. 'Sit down, Cadel,'he commanded. 'There's something we have to talk about.'

Obediently, Cadel sat. There was a burning sensation at the back of his eyes, but he tried to concentrate on what his father was saying. At least, whatever it was, it would take his mind off Kay-Lee. The cruelty! The unfairness!

No. He wouldn't think about that. Not now.

'Cadel, it's your birthday tomorrow,' Dr Darkkon declared. 'You're going to be fourteen.'

Oh yes, thought Cadel dully. I forgot about that.

'Have you decided what you want, son?'

There was only one thing Cadel wanted at that moment. And his father couldn't give it to him.

'Not really,'he muttered.

'Well, there's no hurry,' Dr Darkkon continued. 'When you've made your mind up, you can tell me. Meanwhile, I've got something to tell you. Something I swore to tell you when you turned fourteen. When you weren't a child any more, in other words.'

'But I am a child,' Cadel pointed out, before he could stop himself. 'Legally, I won't be an adult till I'm a'

'Yes, yes, I don't mean under law.' Dr Darkkon's tone was impatient. 'I mean in the truest sense. You may not be an adult, yet, but you're certainly not a child.'

'The Romans didn't think so, anyway,'Thaddeus interjected, and Dr Darkkon flashed him an irritable look.

'Yes, well, that's neither here nor there,' Dr Darkkon said. 'The point is, Cadel, I've something to tell you about your mother.'

'My mother?' This was completely unexpected. Cadel struggled to concentrate. All at once, his heart contracted painfully. 'You don't mean ashe's not alive, is she?' he squawked.

'No. Oh no.'

'Calm down, Cadel.' Thaddeus put a firm hand on Cadel's shoulder. 'It's nothing like that.'

'She is dead, I'm afraid. There's no question about that.' Dr Darkkon's voice cracked, then grew hoa.r.s.e. He cleared his throat. 'But before she died, Cadel a well, you might have wondered about her. What she was like. Why I haven't shown you any pictures. That sort of thing.'

Cadel realised, with growing astonishment, that he never had. He never had given much thought to his mother. Why was that? Because his mind had been fully engaged elsewhere? Because Thaddeus had almost never brought the subject up during their talks? Because both Thaddeus and Dr Darkkon, on the rare occasions when they did mention his mother, spoke dismissively, as if she wasn't of any importance?

'The fact is, son, she left us, before she pa.s.sed away,' Dr Darkkon sighed. 'She abandoned us both. She was taking drugs, and she got involved with the wrong sort of people, and a well, she disappeared. That's all I can tell you.'

Cadel gasped. 'You mean, you don't know what happened?' he squeaked.

Thaddeus, who hadn't let go of Cadel's shoulder, applied more pressure, and leaned down to address his bewildered client.

'What your father means,' he said quietly, 'is that Elspeth vanished, leaving behind all her possessions and what was left of her money. Her purse was found at the bottom of a cliff. No one's seen her since, except the people who killed her.'

'But a but if no one's seen her,' Cadel stammered, 'then she could be alive! Couldn't she?'

'No, son.' Dr Darkkon spoke gravely. 'She was killed. I never found her body, but I found the men who did it. At least, Thaddeus did. He took care of them, too.'

'They disposed of the body,' Thaddeus interposed. 'They told me how, but I won't describe the method. It really doesn't matter.'

'What does matter,' Dr Darkkon went on, 'is that she betrayed us, Cadel. She walked off as if she didn't care. One day she just walked off, and that was that. I never saw nor heard from her again. It was as if we'd never existed.'

'But a '