London.

1972. June.

In the summer the heat gathered in the streets, lingering on street corners and near drains, an amorphous haze rippling on tarmac. The smog from the city would drift north to Hackney, carrying with it the stench of the Thames. Zdan was nine years old and couldn't remember his life before they'd come to London, for he'd been only an infant when they'd journeyed through the portal. He'd seen images of the Blue Towers, paintings and photographs, but could scarcely believe that they were real: a city state of gleaming marble and ivory, water flowing magically from the tops of the graceful buildings to the lake below, each level open to the elements and supporting its own small community. His mother talked about it reverently, as if it had been a dream; his father, less so. It was impossible to imagine the pure waters of Palinor when surrounded by their current reality. His father had been somebody back on Palinor. Somebody that mattered. That's what he always said.

At least the heat meant that his scrappy, threadbare clothes weren't an issue.

There was no school, so Zdan spent his days exploring. He had few friends, at least none who would want to be seen outside of school with a boy of mixed heritage. The previous year he'd tried growing his hair long, to hide the points of his ears, but somehow everyone still knew.

It was late and getting dark. Zdan knew that his parents would start worrying if he didn't get home soon, but he couldn't resist the pull of the abandoned building before him. It was a squat thing, boxy, and surrounded by weeds and stinging nettles. A broken and warped chain-link fence had once kept out potential looters, but there was nothing left to steal. He hopped over the fence's remains, then tip-toed carefully around the thorns and nettle barbs. All the windows were boarded-up but the makeshift wooden planks nailed to one had come away, revealing a black hole through which Zdan could easily squeeze. He dropped silently into the interior, which was a single large room that might once have been a gym. As his eyes adjusted to the gloom, he recognised a raised platform in the middle as the remains of a boxing ring.

He felt the hairs on his arms prick up. There was an uncomfortable feeling of static in the air, like when he took his school jumper off over his head, or if someone rubbed a balloon against their clothing. Something tiny scurried away and disappeared into a crack in a wall. There were paint cans in one corner, as if someone had once had the intention of cleaning up the place. A notion long-abandoned. Though he was on his own, Zdan crept cautiously about the place, as if concerned he might wake the ghosts of whomever had once used it. His father sometimes mentioned how the area had been up-and-coming when they'd first moved there, but that the community centre had closed down, and the library, and the football field.

As he moved around the edge of the boxing ring, Zdan became aware of something very wrong: an irregular black shape, about the size of an adult hand, hovering vertically in the air. It looked initially like a piece of black fabric, perhaps caught on a spider's web or some other thread from the ceiling. As he got closer he could see that was not the case: it was a hole, a void, a nothing-space, about his head-height. He leaned towards it but couldn't make out any details. The odd, floating shape completely blocked his view of his hand as he waved it around behind it. Picking up an ancient paintbrush from the floor, he poked at the hole. The brush's end disappeared into it, as if plunged into thick, black water. Holding it in place, Zdan leaned around the other side of the void, but the brush's tip was nowhere to be seen. It had vanished within the tear.

*

Late shift

On duty: DC Nisha Chakraborty and DC Zoltan Kaminski

London

1972. November.

It was unbelievably cold. The windows of the SDC offices were steamed up on the inside and iced on the outside. Kaminski stood by the gas fire, still wearing his coat, wondering if he should put his gloves on as well. But then he wouldn't feel the subtle warmth from his cigarette.

"How is it," he started, "that this city can melt roads in the summer and be this fucking cold in the winter? Whatever happened to England having a mild climate?"

Nisha laughed from across the room. "Didn't you hear? Global warming. That's all the Max-Earthers seem to talk about."

Kaminski gestured at the frosted window. "Does this look like global warming to you?" He shivered, surprised he couldn't see his own breath despite being inside. "Max-Earthers just don't want us to have nice things. You'd think the factories would warm up the place. Make the smog thicker, that's what I say. Nice and cosy. Like a blanket."

"Then you'd have to find something else to complain about."

"Complaining makes me happy." He sighed, crushed the stub of his cigarette into an overflowing ashtray and lit another. The office was quiet, the early shift having gone home and the night shift not yet arrived. Bakker was still beavering away in his office and Robin was somewhere in the building, but otherwise it was just him and Chakraborty. He joined her at the board. "Got anything useful?"

"Define useful."

"Something which means I can get to the pub early."

She waved a hand at the assorted photographs and written reports. "There's nothing linking them. Other than lots of money lost by gullible people. But, I mean, that's the city. Happens every day."

Squeezing the bridge of his nose between thumb and forefinger, Kaminski sighed. "Why has this case even come our way? It's a con artist, or a gang. Tricking idiots into handing over cash and bank account details."

"Yeah, but two of them claim to have known their fraudster personally, and another four were pretty convinced that they were dealing with legit representatives from other companies."

"Like I said, idiots. Just because all of those suspects have solid alibis doesn't mean they didn't have something to do with it. Or the fraudsters are good at dress-up. Or maybe they look similar. It's not like impersonation is something new."

"I dunno. Remember that one guy," Chakraborty searched the board with her eyes, then prodded at a photo, "here, Mr Richard Kinnear. Investment banker. Knows what he's doing with money, right? He was adamant that the person he spoke to looked exactly like a colleague."

"OK, what are you saying?"

Chakraborty shrugged. "I dunno. Maybe we're talking some sort of Palinese trick spell. Or Max-Earth infiltration tech."

Kaminski's felt his eyebrows trying to lift off his face. "Really? You sound like you've been reading too many bargain bin novels. Can't be a spell, this has been going on for months. It'd have to either be lots of separate people each with a perfect mimic spell, or it'd have to be someone travelling back and forth through the portal each time to re-apply a different look. And they wouldn't get past immigration if they were impersonating someone. Tech, maybe, but seems pretty far-fetched to me. It's not like Max-Earthers need the cash, right?"

She fell grumpily into a chair and started swivelling it round and round. "Can we hand this off to someone else, do you reckon? Maybe Clarke would like it. Nice, quiet case without any drama." She groaned. "Times like this you could do with a little murder. Something you can get your teeth into."

An idea sparked. Perhaps it was the mention of Clarke. "We need a sting operation," he said. "These con jobs have been happening more and more frequently. Maybe we can set one up, lure in whoever is doing it. We'll need someone who looks like a businessman."

"Someone older, then."

"Right. Serious-looking, but not so savvy that he couldn't be duped."

Chakraborty clicked her fingers and picked up the telephone receiver. "I'll give Yannick a call, see if he can come in early."