The creature pushed suddenly and the window disintegrated. There was only a small, dry sound, as if the air was leeched of substance. Nuggets of glass sprayed the room.

Isaac watched, transfixed. He trembled.

At the edge of his vision he saw Derkhan and Lemuel and Barbile in the same state. This is madness! he thought. We’ve got to get out of here! He reached out and plucked at Derkhan’s sleeve, began to pick his way towards the door.

Barbile seemed paralysed. Lemuel pulled at her.

None of them knew why she had said to look in the mirror, but none of them turned around.

And then as they faltered towards the door, they froze again, because the thing in the room stood.

In a sudden flowering motion it rose behind them, filling the mirror into which they gazed, aghast.

They could see the back of Mr. X, who stood and gazed at the patterns on those wings, patterns that rolled with hypnagogic haste, the colour cells under the creature’s skin pulsing in weird dimensions.

Mr. X stepped back to see the wings better. They could not see his face.

The slake-moth held him in thrall.

It was taller than a bear. A clutch of sharp extrusions like dark cartilaginous whips blossomed from its sides and flickered out towards him. Other, smaller, sharper limbs flexed like claws.

The creature stood on legs like monkey’s arms. Three pairs jutted from its trunk. It stood now bipedally, now on four legs, now on six.

It reared up on its lower legs and a sharp tail slithered forward from between its legs for balance. Its face—

(Always those huge irregular wings, curving in strange directions, shifting in shape to fit the room, each as random and inconstant as oil on water, each a perfect reflection of the other, kept gently moving, their patterns changing, flickering in a seductive tide.)

It had no eyes that they could recognize, only two deep sunken hollows sprouting thick, flexing antennae like stubby fingers, above rows of huge slab-teeth. As Isaac watched, it cocked its head and opened that unimaginable mouth, and from it a huge, prehensile, slavering tongue unrolled.

It waved quickly through the air. Its end was coated in clumps of gossamer alveoli that pulsed as the enormous thing flailed like an elephant’s trunk.

“It’s trying to find me,” wailed Barbile, and broke, and ran for the door.

Instantly the slake-moth flickered its tongue towards the movement. There was a succession of motions far too quick to see. Some cruel organic jag snapped out and passed through Mr. X’s head as if through water. Mr. X shuddered suddenly and just as the blood began to well explosively through the sliced bone the slake-moth reached out with four of its arms, pulled him briefly closer and hurled him across the room.

He flew through the air trailing gore and bone-shards like a comet. He died before he landed.