Kingsley woke to the sound of a bell ringing. Not a church bell; it was far more insistent. It took his sleep-befuddled brain a moment to realise it was more like a fire bell and then he bolted out of the supremely soft bed Evadne had shepherded him to after his bath the previous day.

For a moment, he was unsure exactly where he was and that disconcerted him. Bath, bed, he remembered, but his whereabouts beyond that eluded him. He liked knowing where he was. Their arrival was only a fuzzy memory, exhausted and mind-battered as he had been, and confused by his ridiculous dream of a boat voyage. He had vague recollections of heavy rain, crowds of people underneath a field of umbrellas, and another stair-enabled descent, but everything else was a jumble.

He was still fumbling with his tie – clean and pressed like the rest of his clothes – when he found Evadne in a round room, twice as tall as it was wide. She was peering at one of a dozen or so oval windows that were set into the wall like a double row of plaques. Underneath them ran a long shelf with an array of switches, knobs and levers. She was wearing a long green leather coat over a dark blue dress that was piped with cream. She had a small hat, quite the opposite of the fashion, something like a top hat much reduced and much less masculine, probably due to the light blue feather stuck in the band.

When he entered, she glanced at him. ‘Stay there!’ she ordered. ‘Don’t move!’

She left the bank of glasses, disappeared through a door and emerged a moment later hefting a rifle that was a cousin of the pistol she’d used on the hapless police constable: black, sleek and deadly.

‘What is it?’

She ignored him and ran past, disappearing through the door he’d entered by.

A door banged, the bells continued to ring, and all Kingsley was left with was the scent of gardenia in the air.

He went to the door opposite and peered inside. He was confronted by a workshop that looked like a university physics laboratory that had surrounded and taken over a foundry, with power cables strung willy-nilly from roof beams, a brace of workbenches heavily laden with impressive glassware and a row of metal cabinets that looked as if they could take a direct hit from an artillery shell without flinching. For a moment, he hesitated, but the urgency of the bells made him move. He grabbed a bullseye lantern and a shiny metal bar, then set off after Evadne.

Kinsley counted five doors. All of them were open, the last still swinging. He hesitated, reluctant to leave the refuge unprotected, but angry cries echoed down the tunnel in front of him and set him running in that direction.

A stutter of sharp, hard reports came to him, loud enough to hurt his ears. He lurched against the bricks of the tunnel, shivering as the noise of conflict set his wild side on edge. Should he ready to fight, or should he turn tail and run?

Another hammering of gunfire and a chorus of unearthly wails made him bite down on his animal self. His head pounding with the effort, he staggered on, using the metal bar for support and bent over to avoid hitting his head on the roof of the tunnel. He held up the lantern just in time to avoid plunging over the edge where the tunnel gave out onto a shallow, precarious ledge.

Light flashed and a rifle cracked. Echoes swallowed it, tumbled it up with shouts and screeching, a wicked brew of pain and anger. Kingsley swept the lantern and found he’d come to an open space with four or five drains emptying into it – one of which was choked with the rangy figures of those who’d abducted him from the police station.

For an instant, Kingsley pulled back, recoiling from the horrible creatures. Then he crept forward, keeping himself concealed, unwilling to let them daunt him.

The creatures were trapped in the tunnel mouth, pinned by Evadne’s rifle fire, but they weren’t defeated. They howled and shrieked and threw themselves out, tumbling one over another in a battle frenzy, plunging into the pool and floundering forward before Evadne struck them down.

She stood on a small promontory that jutted into the pool, balanced on a pile of broken masonry, a silver-maned Fury. She fired again. The sound of ricochets added to the cacophony, but she didn’t stop. No doubt aided by her light-enhancing spectacles, she fired again, and again with accuracy that bordered on the phenomenal.

She was crying.

The light was poor, but Kingsley could just make out that she was sobbing as she worked the bolt of the rifle, gasping for breath in between tracking the Spawn as they sought her. She dashed tears away with the back of her hand but she held the rifle steady.

Two Spawn threw themselves into the pool, rose roaring and were thrown backward by Evadne’s accurate fire.

Kingsley rose from his crouch, squinting, trying to make out figures moving in the shifting shadows. There, on the other side of the pool – where Evadne had no hope of seeing them from her position out on the promontory of rubble.

He abandoned the lamp. He leaped from the ledge and landed on a narrow, noisome shore. He ran, metal bar in one hand, skirting the pool, aware that if Evadne caught sight of him she could mistake him for one of the Spawn, but not hesitating for an instant – for he’d seen that the two vile creatures had emerged and were creeping up on her, well behind her field of vision.

Kingsley hurdled over a broken wooden crate in time to see the first of these stealthy Spawn rear up behind her. She didn’t have a chance to move – it clawed her from her position. She fell and her spectacles flew from her head, glinting in the sparse light of Kingsley’s lonely lantern on the other side of the pool.

Instantly, Kingsley was there. He swung the metal bar and the Spawn howled as it was driven back. Its companion wheeled on Kingsley in time to meet the bar coming the other way. It folded when the bar caught it across the midriff. Kingsley kicked and it toppled into the pool.

The first Spawn staggered to its feet. This time Kingsley jabbed at it and took it in the throat. It gurgled and joined its partner in the mucky water.

Kingsley reached Evadne. She was dazed and her head lolled from the Spawn’s blow. Panting, muscles burning, he scooped her up, threw her over his shoulder, tucked her rifle under his arm. ‘This is so undignified,’ she mumbled.

‘I apologise,’ he said. More Spawn were assembling at the tunnel mouth. He set off in the other direction, back towards Evadne’s refuge. ‘It seems practical.’

Evadne didn’t reply. Kingsley cast around for her spectacles, couldn’t see them, then set his teeth and began to jog as fast as he could.

He carried Evadne inside the refuge, following her ragged instructions for bolting each of the doors as they went, holding her in his arms so she could see. ‘The viewing room,’ she gasped over the relentless alarm bells. Her face was streaked with grime and looked different without the spectacles. Kingsley wouldn’t have dared say more vulnerable, but he was willing to wager someone else might have.

‘Push that switch up!’ she shouted over the bells.

A dozen switches confronted him on the wall near the door. All of them were large and brass with rubber handles. ‘Which one?’ he shouted back.

‘The green one!’

Kingsley had to use a knee, but he managed to slam the lever home. Instantly, the ringing cut off. She looked him in the eye. ‘You can put me down now.’

She was hardly a burden. ‘Are you sure?’

‘Not really. If you’re willing to carry me around everywhere, I’ll feign a weakness I don’t feel, just for the luxury.’

‘I’ve always aspired to be a human palanquin.’ Kingsley carefully deposited her on her feet in front of the bank of glasses. He was attentive for any sign of injury, but she was steady enough, if a little grimy from the underground skirmish.

Evadne slipped off to the workshop and came back bespectacled. She stood in front of the wall of glasses, scanning them intently.

‘What on earth is going on?’ he asked.

‘It looks as if the Immortals have tracked you here.’ She pointed at the glass. Kingsley came closer and stood next to her. It wasn’t a window at all, not unless they were looking down on a tunnel from a very lofty vantage point. With growing wonder, he realised that each of the glasses showed a different view. In the one Evadne was gesturing at, a dozen figures were crawling through a tunnel on their hands and knees. It was more like a film in a cinematograph theatre than a window, all greys and blacks, but it was clear enough for Kingsley to recognise the spindly forms.

‘They’re like the ones who abducted me at the police station,’ he said.

‘They’re Spawn, the servants of the Immortals.’

‘Kipling’s evil sorcerers.’

‘He knows what he’s talking about,’ Evadne said through gritted teeth. ‘I’d wipe them out in a second if I could find them.’

The intensity of her loathing concerned Kingsley. Where was the insouciant juggler who had befriended him? He’d assumed that she went through life with an attitude of tolerant amusement – the same sort of attitude that had brought her to nominate him as her project. ‘You have a grudge against them?’

‘The Immortals? I’ve never met them.’

‘And yet you want to destroy them.’

‘I’ve heard of them.’ She glanced at him, but quickly turned her attention back to the glasses. ‘And what I heard put them at the top of my list.’ Her voice was both brittle and uncompromising. She touched a brass knob and the view in the glass brightened a little. ‘Leave it at that, Kingsley, I beg of you.’

With difficulty, Kingsley swallowed the multitude of questions that Evadne’s confession – and behaviour – had prompted. ‘What are you going to do?’

‘What I should have done in the first place.’ Evadne reached for another lever and pushed it to the left. Her lips moved silently for a moment, her expression distant, then she nodded when the glass showed the Spawn recoiling, spinning on their heels and scrambling back the way they’d come. They were followed by a surge of water that rapidly filled the tunnel. ‘That should take care of them.’

‘You did that?’

‘A tiny explosive charge in a spot I’d marked earlier, a tunnel about half a mile away, somewhere under Holland Park. They won’t be using that way again.’ She touched her lips with a finger. ‘I do love explosives. I just don’t get the opportunity to use them as much as I’d like to.’

Kingsley wanted to wave a white flag over his head. ‘I need a cup of tea.’