He'd made it all of forty minutes before calling her once she was out of the door, which, by her father's standards, wasn't bad.

Now, though, as her phone rang, no number appeared, and when she thumbed it on, it felt cold to the touch.

"Hello?"

A man's voice answered, conversational, light, friendly. It said, "We're the one with the flaming wings."

"What?"

"By the traffic lights."

She looked up. There were several sets of traffic lights ahead, by the ugly mess that was the Old Street roundabout, a rumbling grey-white place where three boroughs collided like hungover fighting bulls. There were always people waiting at the traffic lights, or walking up a ramp from the tangle of subways below, and at any one moment any number of them could be making a call.

But there was one leaning against the pedestrian-crossing sign beneath the symbol of the walking green man. He looked like someone bored with waiting for a taxi, but he had a phone pressed to his ear and even in the settling night she could see he was looking at herand there were... there were...

"Come on if you're coming," he said and hung up.

For a moment Sharon stood still and did nothing.

She was confident her father wouldn't have approved of her following strange men, but then, without actually forbidding anything, her father had never really approved of much. He'd just quietly hoped that his daughter, in her own sensible way, would come round to understanding why he wasn't happy on her account.

To the left lay the road home, back to Trish (the loud one) and Ayesha (the quiet one) and yesterday's washing-up and bed and sleep, and tomorrow she would go to work in the coffee shop for Mike (the short-sighted one), and nothing that happened tonight would seem real and Magicals Anonymous would be just another Facebook group until the next meeting, and she'd begin to doubt if it had happened, if she'd shaken the hand of a banshee and had dinner with a troll and received a phone call from a man who'd said, "Come on if you're coming" and...

... and he was already crossing the street, heading towards Goswell Road. Which seemed, Sharon thought with a momentary flash of pride, pretty damned arrogant, like he knew she was going to follow, whereas he really couldn't because that was kind of psychopathic, and what the hell kind of girl did he think she was anyway? Besides, she could look after herself...

She could look after herself.

She followed.

Chapter 15.

The Body Is But a Vessel For the Soul Sammy the Elbow, second (maybe third?) greatest shaman the world has ever seen, once listed all the walks of the city. They went like this: Tourist amble with bumbag bouncing and gormless face so that people know you wanna get mugged; rush-hour scamper of the tossers in suits who are way too busy to be late and so you'd better get out of their way; lovers' sidle, hand in hand, the city nothing to them, movement just a way of getting closer together for snogging, yuck; copper's stride of "I own this so bring it on if you dare"; traffic warden's prowl, three in a gang, slow down the parking bay, quick to the next target and a cuppa tea; old lady's waddle and fat man's stagger, schoolkid's skip and Mum's ramble with the heavy buggy; jogger's pain, late man's breathless run, early man's easy lope. Way you walk says everything about you in this city, says who you are, where you're from, what you're doing, what you want, what you'll get. There's only two walks what are any different from any of these, only two walks what matter for shit.

First one is the shaman's walk, which moves at the perfect rhythm of the city, not too fast, not too slow, not owning nothing but not scared neither, the walk of them that belong, with nothing more and nothing less than that, them that are a part of something bigger, the walk which you can't see, because you fools don't know how to look. Beggar King gets it, knows it's not just about the way you move, but the way you think, understands how to walk on the surface of the earth and leave no mark beneath your shoes, but then he's the fucking Beggar King, if he doesn't get it then what the crap does he think he's doing wearing a crown?

Only one other walk worth the business, and only one dude gets it. It's the walk that closes up the gate, it's the wall that pulls the shadows along behind it, and you spot it by the way the pigeons fly, by the turning of the water in the overflowing grate, by the stretching of the light from the lanterns overhead, and by that tingling at the back of your teeth where all your fillings are starting to hurt. Only one guy does it, but it has been done for a thousand years, and that, you ignorant piece of piss, is the walk of the Midnight Mayor.

Chapter 16.

Tread Softly Upon the Earth There was something funny, Sharon decided, in the way the man walked.

Not too quick and not too slow. Not idling but not in a hurry either. He didn't limp or stagger, didn't hesitate about the turns he made but neither did he flap; nor did he walk head down, uninterested in a destination he had reached a thousand times, but seemed to look around constantly as if absorbing a place he'd known as a child, familiar but distant, beloved and suspected all at once. It was a walk which she would have to run to match, yet if she equalled his pace and remained some easy distance behind, it was the precise speed at which it happened.

She hadn't noticed the first few times, which she reasoned must be the pointno one else had noticed either. If you weren't ready for it, then noticing that you'd accidentally turned invisible wasn't as simple as it sounded. Nor was it invisibility as such. It was more... a lack of perception. She walked and, at a certain speed, with a certain movement, a certain state of mind, it was as if she was so much a part of the cityor perhaps...

... the city was so much a part of her?

... that passers-by no longer bothered to make the distinction.

This was that walk now, she realised, played pitch-perfect. But the man walking the walk in front of her wasn't vanishing from sight, as she might have done; rather he seemed to move as if this was his natural state, utterly comfortable and entirely on edge.

She wasn't sure she wanted to catch him up.

They walked, the three towers of the Barbican rising up on the left. Traffic in this part of town longed to use rat-run streets, little cut-throughs and byways, and to discourage such a notion, the council had closed off most of these, or put up bollards, or turned them into oneway routes so that now only the occasional well-read cyclist dared stray from the traffic-clogged beaten track.

It was therefore inevitable that off the traffic-clogged beaten track was precisely where they went.

They turned into Whitecross Street, by day a market selling handmade soaps, hand-reared meats, hand-fermented cheeses and watches that must have fallen off the back of a lorry. By night the shops were shut, and the pavements seemed too narrow for the empty tarmac road. With a policy of, if you can't beat 'em, join 'em, street artists had been invited in to work on the walls of the old houses, or make their mark on the shutters pulled down in front of the pharmacy or stationer, leaving splashes of colour, jagged lines or tag marks, or the image of a fat bulldog with a lugubrious face, three storeys high and unimpressed by all it surveyed.

The man turned again, walking faster now that they were practically alone, daring Sharon to run after him, get too close. She matched his speed and felt the air around her begin to strain as the fine balance between what was seen and what was perceived struggled to know what to make of her stride. She caught glimpses of fire at the end of an alley still not burned out gaslight green in sodium glass smell of frying sound of the street vendor's call incomprehensible numbers at impossible speed... for a pound!

and looked away, deliberately, from all the things that lurked, as out of sight as she was now. That was the major drawback about becoming invisible: all the other invisible things in the city wanted to know if they could join in too.

The man passed a tiny chapel, barely a cabin with a spike on its head, swung south towards the underpass beneath the Barbican, a place where expensive gyms clashed with convenience stores specialising in plantain and cheap fags, then turned again and was slipping through a galvanised steel gate, barbs on the top and a sign on the front that read: 24-HOUR MONITORING IS IN USE ON THIS SITE. Sharon heard his feet clatter on a metal stair as she hesitated, then took a deep breath and pushed on in. A rectangular yard, barely large enough to hold a lonely man's car, was hidden from daylight by high brick walls. A single iron staircase led up to a fire escape whose door was drifting shut behind the man, and there was something here, something...

Missing.

... which she had no better name for.

She stood on the cracked concrete of the yard, and looked up at broken windows, at walls with crumbling mortar, where even the graffiti artists couldn't be bothered to paint. She saw the yellow lichen flaking off the bricks behind the stair, smelt raw sewage from a neglected gutter, saw purple buddleias sprouting from a crack in the wall.

Missing.

A thing missing here.

She put her hand on the stair rail and felt rust, sensed the metal warp and hum beneath her step, thought she heard voices a long way off, and bit her lip and climbed. At the top a yellow sign hung crookedly by only one nail. It read, VISITORS PLEASE RING RECEPTION.

Sharon pushed the door back and the hinges groaned like a mountain trying to move. Inside, thin night-time light bounced off the shattered glass in the windows and formed a pattern of razored illumination across the floor. Among a vista of concrete pillars stood the remnants of machines that no one had bothered to sell, or wanted to buy. Some she couldn't recognise; others hinted at their purpose: great pipes cracked in two, old pedals snapped in the middle, fat rusted wheels where once an engine strap had run; and all now silent. Even the beggars had fled, leaving the odd trace: a burned-out mattress, a crumpled beer can, a torn shopping bag and a note written in charcoal on the walls: DONT FORGET TO TURN OUT THE LIGHT.

She saw straggling ends of cable suspended where once bulbs might have hung, and listened to the drip drip drip of a shattered something at the other end of the floor, and wondered if there were rats here. She thought perhaps there weren't.

"There used to be, you know," said a voice, enormous in the silence, and yet, she suspected, not that loud.

She jumped, holding her bag in front of her like a shield, and shouted, "I know karate!"

A silence ate up her words, like a whale swallowing plankton. Then the voice answered, "Seriously?"

Sharon hesitated. It occurred to her to run, to vanish through the walls, to go back into the city, where, invisible, she would be safe, to walk the walk of all things unperceived, not that she'd ever tried it in an emergency, if this was that, if that was what this turned out to be. But despite its scepticism, the voicemale, young without being innocentsounded almost impressed.

So, "Yeah," she called into the dark, "I know karate and I kick and bite and scream and all sorts of mega-shit and you wouldn't like to screw with me, okay?"

A shadow moved against the blackness, then crossed into the faint light cast through a shattered window. She saw a hint of dirty coat, a mess of dark hair and, somehow, a flash of too-bright blue eyes, impossible in the gloom. "There used to be something here," he murmured. "When you came in here in the dark, it was the thing that guided your hand to the switch. When the machines failed, it was the tick before the bang that told you to get out of the way. When men said, 'Wasn't that lucky?' the thing, whatever it was, laughed and knew there was no luck. It used to be here, and when all else failed, it kept the beggars warm by the fire and made sure the ashes didn't quite go out and the wind through the window didn't reach every corner. Do you understand what I'm talking about?"

"No," blurted Sharon, still holding her bag to her, tense as a samurai ready to fight. "Sorry, no."

The shadow sighed, ran a gloved hand under a badly shaven chinand there it was: a tingling at the back of her teeth, a sensation on the air, a smell like metal trying to burn, just for a second, before it too became lost behind that blue-eyed stare.

"You have to find out what happened to the dog," he said. "It's important."

The words took a while to digest. Then, "What?"

"I'd do it for you," he went on, "but there's... things. Politics, mostly, but also... it's not really my field, you see? I mean, fire, flood, electrical damage, earth splitting in two, no worries, but this... And there aren't many of you, there never have been, it requires such a special state of mind. And I imagine you've got a lot to do, so please believe me when I say it's important. It's more than important. It's the single most important thing you'll do. I mean, I'm told that childbirth is considered kind of the big thing in a woman's life, something we're probably not going to understand, but otherwise, please believe me when I say that there is nothing you can possibly do more vital to the well-being of the city than finding out what happened to the dog."

Silence.

Then, "You don't know many women, do you?"

If it was possible for a facial expression to speak, then even in the darkness his face was a fluent conversationalist. Finally, "Okay, so the childbirth thing maybe wasn't-"

"Also," she said, "there's this thing called email? If you wanted to talk to me about death and destruction and stuff, then you could've tried that. Or even buying me a cup of coffee or lunch or something. I mean, it could've been professional, but all this... kind of blows it. Who are you? You weren't at the meeting."

"No," he admitted. "But I had someone keep an eye out. And actually, while my initial instinct was rather... Well, perhaps on reflection I can see what you're trying to achieve. And I'm sorry about the lunch thing, I really am, but there's people watching and emails are monitored, and I do respect what you're trying to do, although..." His voice rose in indignation. "Although starting a Facebook group called Weird Shit Keeps Happening to Me and I Don't Know Why But Figure I Need Help is not, may I just say, the best way to go about making friends. And did you have to call it Magicals Anonymous? Couldn't you have started a group called something like... I don't know... Self Help for the Polymorphically Dubious? or No Chanting Please or something a little less... in your face? Is that too much to ask?"

Sharon thought, then exclaimed, "Yes! Yes, it is too much to ask. Because I'm sorry, I know I keep coming back to this point, but who the hell are you and what the bloody hell is going on?"

The man sighed again. "Did I mention the politics?"

"Yeah, but that sounded to me like something you say whenever you just want to blame other guys for you being crap."

"I do not; that is totally..." He hesitated, mid-indignate. Then, "Okay, so you may have something there. But seriously, this treading softly thing isn't our style, and while I'm generally an open and honest kind of guy, and I know you may have a hard time believing this, in my experience all that this open, honest groove has led to is serious cleaning bills and writs for damages. So, sorry if I haven't just jumped in there with 'Yo Sharon, there's shit going down, please fix it.' "

Sharon felt herself swallow without meaning to, and murmured, "You know my name?"

"Sure I do," he replied. "You're Sharon Li. You're twenty-two years old. You work in a coffee shop as what I believe we're now meant to call a barista, and you are, Christ knows why, the founder of Magicals Anonymous, a self-help group of the mystically buggered. You're also, in case you're wondering, so far in over your head that I imagine you're soon going to have a hard time working out which way up is anyhow, and you've probably got enough brains to realise it, and though you're a shaman you're clearly not practised enough to recognise the hollow shell of a place, like this building here, where a spirit should once have been, so I'd work on that, if I were you." She thought she saw the flash of a grin in the darkness, then he asked, "Have you considered evening classes?"

"Have I-"

"You seem like you're big on self-improvement, and anyway..." He stopped, his head turning with pigeon speed towards some unseen shadow. Sharon shifted, listening for something more, and thought she heard... maybe just a train passing below?

"The question you have to ask is this." His voice sounded far-off, distracted, his blue eyes were turned elsewhere. "Where did they go? I've done all I can but I'm no shaman. I don't know how to walk down the hidden paths. The spirits of the city are missing and it's not natural and it's not evolution and it's not right and-"

And she heard it and so did he, somewhere outside in the settled gloom, a sound which you hoped would be an engine starting, the slow winding-up of oversized gears and which, as you listened, the more you listened, truth intruded on hope and it became...

"Don't look back," he said. "It wants you to look."

It became...

"Time to go now," he added. "Time to run."

Starting at the very bottom of the register, almost too low to almost too high, it grew and grew and it became from the floor to the sky: hhhhhoooowwwwwillll!!!!

She looked up at the man in the window and there was light in his hands, light on his skin, a brilliant electric blue and he wasn't humannothing human looked like thathe was a thing wearing human flesh, he was a face pretending, a body bursting from something else inside, and as he looked round at her his eyes burned and in them were a million million voices all shouting all as one and she...

... ran.

Chapter 17.

Movement Is Freedom Sharon ran.

She didn't know why and she didn't know what from, but the man in the darkness had said run, and from his back had grown a pair of burning angel wings and she knew they weren't real, of course they weren't real, but they were real to her eyes, which was all the reality she felt she could cope with right now and and she'd had supper with a troll and shaken hands with a banshee and heard a creature howl So now she ran.

She ran straight through the shaman's walk, that place where she became invisible and all the invisible things began to crawl out for her to see. She ran straight through it and out the other side, unseen footsteps running through the night, a gasp of breath heard where there was nothing to be seen; and as she ran, the shadows dragged behind her and the whispers of the things buried just beneath began to creep and clutch their way out from beneath the paving stones, tangle their memories around her legs and tell of Drip drip drip on the cobble stone Spring-heeled Jack jumping over the rafters Ten for a pound, ten for a pound, get 'em 'ere!

Howl!

Howl!!

Howl!!!

And as she ran she felt lighter, thinner, as if she wasn't merely becoming invisible to the eye that saw, but growing invisible in herself, her very matter melting about her, and on the streets there were creatures clinging to the walls, there were finger bones scratching their way out from between the lines of mortar, and a smell of... wet dog?

Something was sticking to her feet. She glanced down and there was a viscous goo on the pavement, coming up from below the pavement, thick and black and not black thick and red and seeping through her shoes, and it wasn't real, of course it wasn't real, she knew it wasn't real, but the streets were bleeding, seeping blood upwards, and the stench! She gagged and nearly fell, briefly flickering into visibility before picking up the pace again and forcing herself on, running, and she thought she could hear something running with her.

In the darkness behind.

A great heaving of lungs.

A great falling of paws.

A great gasping of breath.

A great running monster whose breath stank and whose bellow-lungs pushed out air like She wanted to look but then "Don't look back," he'd said. "It wants you to look."

Traffic surged past Old Street roundabout, but it was far, far away, horses pulling against the reins of the man in the Ford Mondeo who drove them, scuttling thief-boys spilling their Starbucks coffee, time mixing as past and present clashed in silent explosions around her, and she could taste blood in her mouth and knew it wasn't her blood, and see the howling of the thing, of the whatever-it-was behind her, as movement in the air, like heat haze disturbing the sky, but this haze was all around, rippling against the street light and sucking the colour from it and Don't look back. It wants you to look.