She snapped her hand against the air. The space rippled and a bookcase was blasted back, but the accountant was already moving. Then Valkyrie clicked her fingers and Ryan yelped when fire suddenly flared in her palm. He tore off his jacket and flung it over her forearm, batting out the flames.

“What the hell are you doing?” she raged, trying to push him back.

“You’re on fire!” he squealed manfully.

She pulled away from him, her hand still ablaze, and then she flung the fire, but the accountant twisted, impossibly fast, and the fireball missed him, exploded against the side of another bookcase. The accountant darted out of sight.

“Oh,” Ryan said.

Valkyrie backed up against him. “If you see an exit,” she whispered, “you run to it. Understand?”

He nodded.

Something moved above them and the accountant dropped down on to Valkyrie. She cried out and Ryan stumbled back, watched as the accountant grabbed her and threw her like she was nothing. Valkyrie disappeared among the stacks.

Ryan spun, and ran. He didn’t know where he was going, but anywhere was better than where he’d just been. The accountant was following, but he had leaped back up so he was off the ground, gliding from bookcase to bookcase, like a hawk chasing a terrified field mouse.

Then Ryan saw it – a green EXIT sign over a fire door. He changed direction, almost tripped over a cowering man who was hiding in the Reference section, and ran on. He was almost at the door when he glanced back over his shoulder, saw the accountant leaping for him. Valkyrie emerged from the stacks and something was happening to her right hand – it was covered in writhing, moving shadows. She whipped her hand and a trail of darkness reached for the accountant, wrapped around his leg. Valkyrie pulled back, hard, and the accountant crunched to the ground.

He snarled, sprang up and turned, and Valkyrie sent a wave of shadows crashing into him. He hit the far wall and that’s all Ryan saw, because Valkyrie was pushing him out through the fire door. The alarm wailed as they emerged into the narrow alley behind the library. With Valkyrie’s hand pressing into his back, Ryan sprinted towards the road. A gleaming black car was parked illegally, like it was waiting for them. It looked old, but a brand-new kind of old.

Valkyrie opened the door, bundled him in the back. She got in behind the wheel, leaving the door open. She started the car and the engine roared, and she slipped into the passenger seat and buckled her belt.

“Seatbelt,” she ordered.

Ryan buckled his seatbelt. He looked at the empty driver’s seat. “Does it drive itself?” he asked.

“Don’t be thick,” she replied, looking back at the library. “He just hates it when I drive the Bentley, that’s all.”