Marine worms

Marine worms are among the threats that make the ocean’s depths a contested and poorly understood world in the novel. They are treated as distinct from the Yrr, yet their sudden disappearance coincides with the end of the wider marine attacks; the story gives no definitive explanation for their behavior or for whether that reprieve will last.

An ocean beyond ordinary knowledge

The novel places marine life within an environment that resists the familiar measures of land. Continental shelves are shallow continuations of the continents, but beyond their edges the seabed falls or slopes toward depths described as more mysterious to science than outer space. At sea, the horizon can dissolve into water and cloud, leaving few visual markers; below the surface, familiar senses become unreliable, and at great depth even the distinction between rising and falling depends on instruments. This geography makes the worms part of a realm that humans can enter and study only imperfectly.

The ocean’s hidden terrain is also capable of sudden, large-scale change. As the Thorvaldson struggles through stormy seas, a section of continental shelf and slope slides into deeper water. The displaced mass lowers sea level across a vast area and sends a wave outward, initially so low amid the storm that it goes unnoticed. The episode does not identify the worms as the cause of the slide, but it shows how events in the deep ocean can produce consequences far beyond the place where they begin.

A threat distinct from the Yrr

In a confrontation over the proposed destruction of the Yrr, Sigur Johanson challenges Judith Li by asking how her plan would deal with the worms as well as the dangers already being discussed. Li answers that they would poison everything after eliminating the Yrr, so that humans could do as they wished beneath the sea. Johanson warns that such poisoning would harm humans too. The exchange places the worms within the same political and ecological crisis as the Yrr, while making clear that Li’s proposed solution does not distinguish carefully among the forms of life it would affect.

The novel does not, in the evidence presented here, explain the worms’ anatomy, organization, or precise relationship to the Yrr. Their mention in the argument matters nonetheless: even if one enemy could be removed, the oceanic problem would not thereby be solved, and a weapon aimed broadly at life below the surface could create further danger.

Disappearance and unresolved aftermath

After the USS Independence sinks, the attacks stop. The SOSUS arrays register Scratch signals audible across the ocean; a rescue team later reaches Gerhard Bohrmann’s underwater cave and finds that the sharks have gone. Whales return to their ordinary routines, the worms vanish along with the jellyfish and other toxic creatures, and crabs cease invading the coast. Meanwhile, the oceanic pump gradually resumes, and the methane hydrates begin to stabilize.

These changes occur together, but the account does not establish that the worms themselves caused the crisis or explain why they disappear. The timing links their absence to the broader cessation of attacks without resolving what prompted it. The ending therefore leaves the ocean’s apparent recovery conditional: the immediate danger recedes, but the possibility that it has only been suspended remains.