She pulled away. 'Is that it?' she asked. Her voice was vibrant with suppressed emotion.

The Doctor seemed not to notice. 'Yes, I think so. A pretty good result considering. All over -'

'Doctor!' Tegan screamed at him, her whole body tense with anger.

'- bar the shouting.' The Doctor frowned, his eyebrows knitting together as he leaned towards her. 'Yes?' he asked irritably.

Tegan turned away, arms folded.

'What is it?' The Doctor asked the group collectively. 'What's wrong with her now?'

'I think she might be worried about Nyssa,' Atkins suggested quietly.

'Nyssa? Oh yes, I nearly forgot.' The Doctor fumbled in his pocket and drew out the TARDIS key. 'Well, let's go and wake her up then.'

The old woman who had woken in the sarcophagus followed the Doctor to the TARDIS. It was only after he had unlocked the door and ushered her in ahead of him that he seemed to realize that n.o.body else was following.

They were standing open-mouthed, watching him from the other side of the dais.

'Well, are you coming or not?' he demanded.

Tegan and Atkins looked at each other in silence.

'May I be permitted to ask what's going on?' Atkins had followed Tegan into Nyssa's room only to be confronted with yet another puzzle.

The old woman he had been told was Nyssa was sitting in a chair beside the bed. She patted the hand of the young woman who lay on the bed. A young woman who might have been her grand daughter, except that even across the years between them the resemblance between the two was uncanny.

A small piece of machinery that looked like it was cobbled together out of wires, small boxes and ceiling wax sat humming quietly to itself on the floor beside the bed. The Doctor was just disconnecting it from the young woman on the bed as they entered. As he switched off the machine, the hum died away. And the young woman yawned and stretched.

'That's the delta wave augmentor, isn't it Doctor?' Tegan asked.

He nodded, without taking his attention from the sleeping woman. 'Yes.

Though I had to rig up another delta source to replace the sonic screwdriver, of course.'

Atkins coughed politely. 'Doctor, I take it that this young woman is your friend Nyssa. But perhaps you could introduce us all?'

The Doctor stepped back from the bed, apparently satisfied with Nyssa's progress. 'Of course,' he said. He turned to the old woman. 'Do forgive me, but things have been a little hectic for formal introductions.'

'Not at all, Doctor. I quite understand.' She let go of Nyssa's hand and stood up.

'Tegan, of course, I know already. But your other friend?'

'Mister Atkins.'

Atkins inclined his head slightly. 'Delighted, er -'

Tegan was frowning. 'Do I know you?'

'Of course, my dear. And you haven't changed a bit.' The woman smiled, and the way her face suddenly brightened made her look younger. 'Though I must confess, I have.'

Tegan shook her head slowly. Then her mouth dropped open. 'Ann?'

The woman nodded. 'I'm Lady Cranleigh now. Have been for a very long time. The Doctor came to the wedding, you know?' She smiled at him, and he beamed back.

'When?' Tegan asked.

'In nineteen twenty-six,' Lady Cranleigh said.

'About three hours ago,' said the Doctor.

Atkins coughed politely.

'Ah, yes. An explanation.' The Doctor shuffled his feet uncomfortably. 'Well, this is Lady Cranleigh, nee Ann Talbot, an old friend.' He paused, apparently embarra.s.sed by his choice of words. 'Forgive me,' he said to Lady Cranleigh.

'Of course. But you're right.'

The Doctor continued. 'Ann was the image of Nyssa when we first met.

Even I couldn't tell them apart. So I asked Lady Cranleigh if she would do me a small favour and stand in for Nyssa.'

'So she was in fact merely feigning sleep?' Atkins asked.

Lady Cranleigh laughed. 'I had to lie very still and wait for a pa.s.sword from the Doctor. All terribly exciting.'

'Yes, I do apologise for the melodramatics. And for not telling you all what was going on. Especially you, Tegan. But I had to make sure that Nephthys was convinced that this was Nyssa, and that she had been semi-awake, just enough to age, for seventy years. Ra.s.sul would never have believed I could do it if your reactions weren't genuine.'

Tegan said, 'So when Nephthys looked in Ann's head for the other half of her own mind -' 'It wasn't there, of course.'

'And she thought it had sort of evaporated in nineteen twenty-six and went back to look for it?' Atkins asked.

'Exactly.' The Doctor punctuated the word with a stab of his index finger.

'And when she found Nyssa was still asleep, she sort of bounced back?'

The Doctor nodded. 'She was able to tell when Nyssa would wake, so she came forward to that point. But because she could only act on instinct and impulse...' He left the thought unfinished for them.

'She kept going back and forth in time till she aged to death.' Tegan laughed.

'Simple.'

'Sometimes, Tegan,' the Doctor said, 'you take my breath away.'

'And what, Doctor, happens now?' asked Atkins.

The Doctor picked up a canopic jar from the floor under Nyssa's bed. 'Well, if you'll excuse me just a moment, I think Nyssa is about ready to wake up.

And there's something in her mind I would like to remove.' The top was shaped into the head of a jackal, and he gave it a sharp twist to unscrew it.

'Osiran technology, complete with generator loop.'

'With what?'

'A sort of forcefield,' he explained. 'I picked it up at the British Museum on the way to collect Lady Cranleigh. Wouldn't have worked for Ra.s.sul and his friends, though. But now that I've built in a few modifications and refinements it should be up to the task.'

'Ra.s.sul? I thought he was the bad guy.'

'Oh, indeed.' The Doctor held the jar up and inspected it as if he had never seen it before. 'But initially he was the "guy", as you say, that Horus left to guard the tomb. When Nephthys' energy leaked out, she used his suppressed guilt at sacrificing his daughter to turn him against Horus and into her servant. Quite handy from her point of view, since Horus was already expending the energy to keep him alive.'

The Doctor held the open jar close in front of Nyssa's face, a wire from the cat's cradle contraption he had been fiddling with earlier was connected to the base of the canopic jar. Suddenly, the Doctor snapped his fingers. The noise was like a pistol For a moment they burned with a brightness and intelligence which almost radiated with intensity. Then they dulled slightly, and she blinked. The Doctor jammed the stopper on the jar, and twisted it shut. Then he pulled away the wire and gave a loud exhalation of relief.

'Doctor?' Nyssa lifted her head slightly from the pillows. She looked up at all the people crowding round her bed. 'What's happening?' Her eyes flickered, and she yawned. 'I've had the strangest dream,' she said.

The Doctor smiled. 'Don't worry about it, Nyssa. Everything's fine now.'

Nyssa seemed to have drifted back into sleep, and the Doctor waved everyone from the room. 'I know it seems odd,' he said as he led them back to the console room, 'but she'll be quite tired, I think. She might sleep for a little while.'

Tegan looked sharply at him.

'I mean, maybe an hour or two.'

It seemed as if, despite his frequent protestations, the TARDIS was becoming a taxi service. The Doctor had taken Lady Cranleigh back to Oxfordshire. Atkins had bid a sincere farewell, actually with tears in his eyes, before leaving them outside the back entrance to Kenilworth House a century earlier.

Nyssa was feeling rather weak and drained, so Tegan explained what had been going on. Nyssa seemed to be taking the news with characteristic composure.

The Doctor welcomed the few moments he had to himself. He looked back at the TARDIS, shimmering in the intense dry heat, then continued on his way. He half ran, half slid down the sand, remembering his similar descent with Atkins earlier.

The empty sh.e.l.l of the pyramid afforded some relief from the efforts of the sun, but the air was still close and hot. When he reached the area that had been the main burial chamber, he calculated the position of the point on the floor he was looking for. He couldn't be sure, of course, but the Osirans put a lot of store in geometric patterns and exact points in s.p.a.ce. Horus must, he reflected as he started to dig into the sandy remains of the floor with his hands, have chosen this place for a reason.

When the hole was big enough, the Doctor carefully placed the canopic jar inside. Then he covered it over with the sand he had scooped out. He stood, bowed slightly, and made the Sign of the Eye.

As he left the main door of the pyramid, it swung slowly shut behind him.

When the Doctor reached the TARDIS, he turned and looked back into the crater in the sand. He nodded in quiet satisfaction, and opened the TARDIS door.

The TARDIS shimmered in the heat of the day, and faded from existence.

A moment later, a trickle of sand started running down the crater sides.

Perhaps the Doctor had dislodged it, perhaps the TARDIS had shaken the ground slightly as it left, perhaps there was a sudden inexplicable breeze skitting across the desert. But whatever the cause, the trickle grew into a river of sand flowing down into the crater. Before long it was an avalanche, filling the bottom of the hollow. By the time Orion rose in the night sky, all signs of the black pyramid of Nephthys were buried deep beneath the shifting desert sands.

'Did you find him all right?'

It took Atkins a few moments to realize what Lord Kenilworth was asking him. It was a long while since he had departed to deliver an invitation to the Doctor outside the British Museum. He smiled. 'Indeed, Sir. And I must say I'm very glad I did.'

Kenilworth grunted. 'Didn't take you long, didn't think you'd be back till after I'd turned in.'

Atkins smiled and watched his employer start up the stairs. Then he continued on his way to the kitchens. He felt a nervous excitement above and beyond anything he had experienced during his time with the Doctor and Tegan, and his throat felt as dry as if he were still in the desert.

Miss Warne was standing by the stove. She was stirring a saucepan of soup.

Atkins watched her from the doorway for a while. Her mind was obviously not on the task in hand. She was staring off into s.p.a.ce and humming quietly. Atkins shook his head, such a lack of proper decorum and deplorable laxity of att.i.tude.

'Miss Warne,' he called across the room.

She flinched, and turned. She had stopped humming at once, and her stance was somehow more upright and proper. But in her eyes saw a flicker of emotion, a moment of suppressed happiness.

'I didn't realize before,' Atkins said as he crossed the room, 'just how long you must have been prepared to stand here and stir soup on the off chance that I should remember your kind offer and avail myself of it.'

'I don't mind waiting up.' If she was surprised at his comment, she hid it well. Her head was tilted slightly to one side so that the dark hair fell away slightly. Atkins could see the edge of her ear beneath. He did not remember ever having seen her ear before, and he was struck by how round and perfect it looked. Pale skin beneath dark hair.

'If I didn't know better,' Atkins said, leaning over her shoulder to inspect the soup, 'I might think that you enjoyed waiting for me.'

'If you didn't know better.'

Without changing position, Atkins looked up from the saucepan. His face was close to hers, and he could see that her pale skin was now slightly more pink than a few moments previously. He looked deep into her large, dark eyes.