Bastard John and the Bask menfish followed it, unable to match its effortless pace. In shock, Tanner kicked toward them pointlessly, the memory of the monstrous fish’s presence slowing him and making him cold. He was vaguely aware that he should surface, should keep himself warm and drink sweetened tea, that he felt sick and very frightened.

The dinichthys was heading down now, into the realms of crushing pressures its pursuers could not hope to survive. Tanner watched it go, moving slowly, trying not to breathe in any dissipating blood. He was alone now.

He dragged himself through water like tar, up past unfamiliar undersides, disoriented and lost. He could still see the dead man’s face and slick bowels. And as he found his bearings, as he twisted and saw the mobile ships in Basilio docks and the sprinkled crumblike boats of Winterstraw Market, he looked up and saw in the cold lancing shadow of the boat above him one of the huge, vague shapes that dangled from the city’s undersides, that was obscured by charms and carefully guarded, that he was forbidden to see. He saw that it was linked to others, and he drifted higher, unchallenged now the shark that had guarded it was dead, and the shape was clearer, and suddenly he was close, he was only a few yards from it, and he had penetrated the murk and the obfuscatory hexes, and he could see it clearly now, and he knew what it was.

The next day, Bellis was treated to lurid descriptions of the monster’s attack from several of her colleagues.

"Gods and fuck above," said Carrianne to her, appalled. "Can you imagine? Sliced in pieces by that bastard?" Her descriptions became more grotesque and unpleasant.

Bellis did not give Carrianne her attention. She was thinking about what Silas had told her. She approached it as she did most things-coolly, trying to grasp it intellectually. She searched for books on The Gengris and the grindylow, but found very little that was not children’s myths or absurd speculation. She found it hard-impossibly hard, almost-to grasp the scale of danger to New Crobuzon. All the years of her life the city had squatted around her, massive and variegated and permanent. The idea that it could be threatened was almost inconceivable.

But, then, the grindylow were inconceivable, too.

Bellis found herself truly alarmed by Silas’ descriptions and his obvious fear. With a kind of morbid extravagance, Bellis had tried to imagine New Crobuzon after an invasion. Ruined and broken. It started as a game, a sort of dare, where she filled her mind with horrifying images. But then they flickered through her unstoppably, as if projected by a magic lantern, and they appalled her.