'Oh, Zouche, that's terrible,' said Dalia. 'I'm so sorry. I didn't know.'

Zouche shrugged and stared beyond the glass of the compartment. 'How could you? But it doesn't matter. Tang's dead and the Emperor guides us now. People like Tang won't ever rise again now that the Imperium's in his hands.'

'You're not inferior,' said Dalia, cutting across his train of words.

'What?' he said, looking back at her.

'I said you're not inferior,' repeated Dalia. 'You might think you are because you look different to the rest of us, but you're not. You're a brilliant engineer and a loyal friend. I'm glad you're with me, Zouche. I really am.'

He smiled and nodded. 'I know you are and I'm grateful for that, but I know what I am. You're a good girl, Dalia, so I'd be obliged if you didn't mention this to anyone, you understand?'

'Of course,' said Dalia. 'I won't say a word. I think the rest are going to sleep all the way there, anyway.'

'Quite probably,' agreed Zouche, a discreetly extended mechadendrite linking with the port in the compartment's wall. Flickering light ghosted behind his eyelids as he linked with the mag-lev's onboard logic-engine. It was easy to forget that the Mechanicum had substantially modified Zouche, for most of his augmetics were subtle, and he was reticent about openly displaying them to one not of the Cult Mechanicum. 'It's going to take us two days to reach the point nearest the Noctis Labyrinthus, an outlying hub of Mondus Gamma in the northern Syrian sub-fabriks.'

'Two days? Why so long?'

'This is a supply train,' explained Zouche. 'We're going to pass through a lot of the borderland townships on the edge of the pallidus. According to the onboard timetable, we're about to reach Ash Border, then we'll pass through Dune Town, Crater Edge and Red Gorge before we begin the descent to the Syria Planum and Mondus Gamma.'

'Not big on originality when it comes to their settlement names, are they?' observed Dalia.

'Not really, I suppose they just name it as they see it,' said Zouche. 'When you live out on the edge of civilisation, there's a virtue in simplicity.'

'I think there's a virtue in that wherever you are,' said Dalia.

The hab was warm, but then it was always warm. Hot air rising from the magma lagoon rolled up the flanks of the volcano in dry, parching waves to leach the moisture from the air like a giant dehumidifier.

Mellicin lay on her bed, with one hand thrown over her forehead. Sweat gathered in the spoons of her collarbones and she felt uncomfortably sticky and hot. The atomiser was turned on, but might as well have been switched off for all the difference it was making. She rolled onto her side, unable to sleep and unable to stop thinking of what might be happening to Dalia and the others.

She told herself it wasn't guilt, but only half-believed it.

Zeth had placed her with Dalia with the express purpose of passing on her impressions and insights into the young transcriber's mind, and that was exactly what she had done. There had been no betrayal, no breach of trust and certainly no disloyalty.

The only betrayal would have been if she had failed in her duty to her mistress.

Why, then, did she feel so bad about telling Adept Zeth of Dalia's plans?

Mellicin knew exactly why she felt bad.

In the weeks she had worked with Dalia Cythera, Mellicin had rediscovered the joy of working on the frontiers of technology. Together they had discovered new and wondrous things, devices and theoretical science that they had gone on to prove valid. How long had it been since she, or indeed anyone in the Mechanicum, had done that? True, Adept Zeth was forever pushing the boundaries of what was known and accepted, but she was a tiny cog in a larger machine and there was only so much she dared risk.

The Mechanicum was old and unforgiving with those who disobeyed its strictures.

They had been gone less than a day and already she missed them. She wished she knew where they were so she could have tapped into the Martian networks to follow their progress, but she had wiped Dalia's destination from her memory coils.

Right now, they could be anywhere, en route to the far side of the planet for all she knew.

Mellicin had got used to their foibles, strengths and blind spots. She had nurtured them, blended them together until they were a team, working more efficiently and more enthusiastically than any of them had ever worked before.

Now they were off making good use of that mentoring and she was left behind.

She swung her legs out of bed and ran a hand through her hair. It was matted and sweaty, and no amount of time in the sonic shower would make it feel clean. She padded softly from the bed alcove and made her way to the kitchenette to fix a pot of caffeine. If she wasn't going to get any sleep, she might as well use the time productively.

She yawned as the heating ring fired the pot, wiping sweat from her brow as the pot bubbled and hissed. She poured a cup and sat in the dining nook within the polarised glass bay that looked out over the surface of the red planet.

This high up, Mellicin was above the distorting fumes that filmed the lower level windows with grime and pyroclastic deposits. Far below her, the Magma City blazed with light, an ocean of glowing industry in a desert of industrial wasteland. Silver trails of mag-levs spun out from the city, ttavelling to all parts of Mars, but beyond them the planet was shrouded in banks of dust and polluted fogs.

Mellicin put down her cup and leaned her forehead on the hot glass. Lights moved in the city, and glittering transits ferried cargo and supplies to the port facilities.

'Wherever you are, Dalia, I wish you well,' she whispered, feeling very alone.

She frowned as she realised she wasn't alone.

Her biometric surveyors were reading another life form in her hab.

'I was wondering when you would notice me,' said a voice from the shadows.

Mellicin jumped at the sound, looking up in frozen surprise as a lithe, sensual woman glided from the darkness. She was clad in a skin-tight red bodyglove and a pair of finely-wrought pistols were sheathed at her hips.

Mellicin covered her surprise and said, 'I knew you were there, I was just waiting to see when you would announce yourself.'

'A lie, but one necessary for you to feel you are still in control,' said the woman.

'Who are you, and what are you doing in my hab?' asked Mellicin, still too surprised to feel anything but annoyance.

'My name is irrelevant, because soon you won't remember it,' said the woman, and as she moved into the light,

Mellicin saw the golden death mask she wore. 'But for the record, it is Remiare.'

Mellicin's annoyance turned to fear as she realised what this woman was. 'That's half my question answered.'

Remiare cocked her head to one side and said, 'You still think you have a measure of control, don't you?'

'What do you want?' asked Mellicin, pushing herself further into the dining nook.

'You know what I want.'

'No, actually,' said Mellicin, 'I don't.'

'Then I shall tell you,' said Remiare. 'I want you to tell me the whereabouts and destination of Dalia Cythera.'

Mellicin furrowed her brow, as if in thought, and activated her silent alarm. Adept Zeth would now be aware of her plight and a squad of Mechanicum Protectors would soon be despatched to her rescue. All she had to do was stall.

'Dalia?' she said at last. 'Why do you want to know about her?'

'No more questions,' said Remiare. 'Tell me what I want to know and I promise you won't suffer.'

'I can't,' said Mellicin. 'Even if I wanted to. I might have known what you want, but I don't remember anymore.'

'You're lying.'

'I'm not. Adept Zeth had me erase any knowledge of where Dalia was going from my memory coils.'