That would be enough to make the magicians come to the windows, and enough to make them afraid. They didn’t know how far the pipers’ power over these people would extend.

Nor did Sin, actually. When she had inquired, Matthias had said, “I could pipe them into the sea,” and added, “Hadn’t you heard? Pipers steal children.” When she asked for him to stop talking nonsense and children’s stories, he had laughed and walked off, piping already. She’d found her hand tapping a rhythm before she recalled that she danced to no tune she did not choose.

As far as the magicians were concerned, pipers might well be able to pipe people into the sea and steal children, and create an army to fight them.

Sin heard something else, too. She heard the rustle through the bushes in these houses’ front gardens, the sound of dragging bodies through the grass in the back, and she knew the necromancers had sent every crushed piece of roadkill, every frozen cat curled beneath a bush, every drowned dog with a bloated belly in the Knightsbridge area staggering toward the magicians’ house.

The railings running along the houses burst into blue flame that the potion-makers had assured them would burn hot and fast, and that the magicians would not be able to put out.

Sin heard the front door of the house slam open, heard the commotion in the garden, and felt fiercely proud.

Now that the Goblin Market had come out of hiding, they were more powerful than the Circle had ever dreamed.

Sin rose cautiously, still crouched, and saw Nick rise on the other side of the roof. They gave each other a nod and a flashing smile, and then Sin tucked herself into a ball and rolled easily, head over feet, until she reached the magicians’ roof.

She stood at the edge of the roof, testing it, and jumped. She caught the gutter with both hands as she fell, swinging easy, and found the windowsill with her feet. She rested her toes against the sill, and when there was no sign of it giving way, she knelt down and tested the window. It was locked.

Sin sighed at magicians and their apparent conscientiousness about home security, and stretched back up on her tiptoes to grab the gutter again. She flexed her back and locked her legs together, making herself a pendulum, gathering force and speed.

She crashed through the magicians’ window feetfirst. Her shoes and jeans caught most of the damage, though she felt the swift, hot sting of a cut opening on her cheek as she landed on a wooden floor amid broken glass.

She had as much luck with the room as with the window. Which was to say none.

There was a magician in it, a young man drawing a circle, obviously wanting more power before he joined in the fight outside.

Well, she’d brought the fight in to him.

Sin drew her knives and threw one as the magician leaped to his feet and deflected the knife with a shimmer of magic rising from his palm.

Sin did not risk throwing her other knife. She eyed him warily. He eyed her back just as warily. Throwing knives always got people’s attention, but she would have preferred to see him a little more relaxed, a little more certain he could beat her. She could’ve used that.

Instead he threw a pale fireball at her, and all she could do was dodge.

She dodged and ducked, making a bigger production of it than she had to, trying to draw his eye with unnecessary movement. She used fancy footwork in the mess of shards and gleaming splinters of glass, silver sweeping in her wake as she lunged and retreated meaninglessly, making battle a dance.

His eyes went to her feet for a second. Sin threw herself forward and slid her knife up under his ribs, a sure and swift killing blow. He doubled over against her, his blood spilling hot on her hands, and Sin pulled her knife out and stepped away so his body fell heavily onto the floor. There was a sickening crunch as if he’d broken his nose, but that hardly mattered now.

Sin jumped over his body and went for the door, out into a long hall full of dusty pictures. She ran under a chandelier in the shape of a dream catcher, the carved crystal hanging dull and dim, throwing open every door in the corridor as she went.

She could hear running feet and slamming doors, and did not know which sounds were her allies, intent on the same task as she, and which the magicians running to fight them.

When she opened the next door, one opposite a charmed tapestry inscribed with rings, crowns, and jewels, it didn’t matter.

The room beyond was vast, with a vaulted ceiling and a glossy wooden floor that bore twelve of the most perfect summoning circles Sin had ever seen, the lines of communication that translated demons’ silent language into speech straight and true, the circles within circles smooth. There were pairs of circles overlapping each other, like dancers’ circles, as if to make more room for the demons. Even the circles not currently occupied gleamed with subtle fire, with a shimmer like the reflection of the magical stones for which the magicians’ Circles were named.

The circles with demons in them were brimful of brimfire, and the demons inside them were negotiating with the magicians. Sin saw Gerald, Laura, and Helen, their faces almost obscured by flame, intent on the demons.

Sin put her hand into her pocket and took out a beacon light, so small it was like a glowing pearl in her palm. Then she closed her eyes and crushed it in her fist.

Light erupted from her hand as if she held lightning trapped in her fingers, the shuddering shock of brightness painting the insides of her eyelids with violent yellow streaks.

Sin opened her eyes.

She’d given the signal. Everyone who could come would be coming soon.

Not soon enough, she realized, as she saw Gerald’s face.

The fireball only just missed her as she threw herself onto the ground, tumbling head over feet and landing crouched behind more balefire.

It might be a good cover for her, but she didn’t want the magicians to have any more power.

“Thalassa, who loves the sea by night and drowning by night better,” Sin shouted. “I dismiss you!”

Name the demon, and you controlled it. The balefire screening her began to ebb and dim, and as she performed another roll she shouted another name.

“Mafdet the clawed, I dismiss you!”

She couldn’t keep this up. Where was everybody?

“Amanozako the blade-eater,” said Jamie from the door, as if she had called him with her need. “I dismiss you.”

Gerald stopped hurling fireballs at Sin. For a moment, all he did was look at Jamie, standing in the doorway with Mae at his shoulder. Jamie was wearing the clumsy hook they had got him because they didn’t have time to make anything better.

There was blood on it.

The pause gave Sin a moment to look at Gerald. He looked terrible in a way that went beyond the battle her Market had brought to him. He was very thin, attenuated as if his own flesh was being eaten away from the inside out. This was no smug villain, Sin thought. He looked like a torture victim.

He cared about Jamie. She’d known that much before, that they must have been friends at some point, that Gerald had believed in him.

He’d killed and schemed and sacrificed his friend for power, and look what good it had done him.

Jamie seemed to see the same thing Sin did. He paused with his hand uplifted, as Gerald had, and he looked sorry.

There was a commotion in the corridor. When the door opened again, there were more magicians behind it.

Sin’s hand closed convulsively on the handle of her knife.

There was light like a starburst in the corridor, and the sound of steel. Sin could see heads falling from view, magicians being cut down, and a path being carved out.

Into the room with the other magicians came a band of Market people and pipers, necromancers and messengers, and in the lead Nick Ryves.

Nick had his sword out, blood running down the steel. He moved so Mae was between him and Jamie, shielded as much as she could be, her pocketknife clasped in her hand. Jamie’s hand and hook were suddenly shimmering like his eyes, his whole body obscured by a haze of power.

“Gerald,” Jamie asked imploringly. His face was pinched and pale, full of dread. “Will you surrender? Please.”

Gerald laughed at him.

“We can all live,” Jamie continued as if he had not. “Give me the leadership of the magicians, and you can go in peace. You can live.”

There was a stir among all the magicians, as if they had not expected Jamie to ask for this.

“You want my Circle?” Gerald demanded, and then laughed again. “I told you, didn’t I? I always told you, no matter how much power you have, you’ll always want more.”

“I want the Circle to join the Market,” Jamie said softly. “You could too, if you wanted.”

“I swear you could,” said Mae, who always had her brother’s back.

Gerald laughed again, the sound scraping Sin’s ears like a shriek. “You’re such an idiot,” he told Jamie. “You’re a child, and you’re dreaming. Even if I wanted to try, it wouldn’t work.”

“I’m going to try,” Jamie said. “But I wish you could live.”

Jamie advanced, nobody else in the room moving, magicians and Market all still because nobody was quite sure what was happening anymore, and everyone knew that one move would throw them all into bloody chaos.

Jamie kept coming. Nick and Mae followed behind, not at his side, not openly threatening, but in a silent promise of defense. Gerald watched Jamie come, and watched Jamie beckon to Nick.

Nick leaned in toward Jamie, black head bowed deferentially, and Jamie’s eyes flashed with a fresh wave of magic.

Jamie had hoped Gerald would surrender. Sin had not until she saw Gerald, and then she had thought that perhaps, just possibly, it might be so, that Jamie’s dream could come true, that they could all walk away from this with clean hands.

“Kill him,” Gerald ordered his magicians. His voice was deliberately emptied of emotion, not like a demon’s innate lack of human emotions, but as if he had human emotions and had poured them away. “Kill Jamie, and the demon is mine alone to command.”

He threw a slash of magic at Jamie, like a black lightning bolt. The air froze in front of Jamie’s face, ice absorbing the lightning and falling into glittering shards on the ground.

“You think so?” Nick asked.

He pushed Jamie aside and walked forward, taking one step, then another, across the polished wooden floor and into one of the overlapping magicians’ circles.

“Stop,” Gerald commanded, and Nick stopped. Gerald’s smile spread.

Jamie opened his mouth to speak.

“What are you going to do, Jamie?” Gerald asked. “You gave me control over it too. I can say ‘stop’ and you can say ‘go’ until we tear the thing to pieces between us. But you won’t, will you? Because you care about it, and I don’t.”

He reached out a hand toward Nick.

It felt as if the room had turned into a desert, the heat scorching and no moisture in the air, with silence all around.

Nick went blazing white, and so did Gerald’s eyes.

Gerald advanced on Jamie, and light rose between them like a path for them to follow. They both walked the path to each other, and it seemed like the desert winds howled.

But it wasn’t wind. It was magic, called not only by Jamie and Gerald but by all the magicians, filling the air with sound and light.

A magician, built and buzz-cut like a soldier, threw himself into their midst and caught up Mae. Mae sliced her knife across his arm, and Sin grasped his hair and slit his throat.

The sound of the pipers was lost under the howl and hiss and whine of magic everywhere, and there was no time to look to Jamie. Nick was on his knees, going paler and paler until he was gray, as if he was being leached of blood instead of magic.

“To Nick!” Mae commanded the Market, someone else’s blood red in her pink hair.

Sin ran, faster than anyone else, to stop Helen before she reached the demons’ circles where Nick was kneeling. She threw herself against Helen, pressed close so the reach of Helen’s swords was no advantage at all, and steel met steel.