The metal Coffin

When analytical consultant Elias Crowe is recruited by a secretive government maritime division to investigate unexplained ship disappearances, he expects faulty sonar, natural anomalies, and human error.
What he gets instead is the Metal Coffin-a windowless deep-sea submersible designed not to see, but to listen.
As Crowe descends into an impossible ocean trench where depth no longer behaves like distance, he uncovers fragments of a truth buried beneath layers of classified directives, altered logs, and a shadow organization known only as The Listeners-a cult embedded within the government that believes something ancient beneath the ocean is not a god, but an archivist of reality itself.
With every descent, the entity responds faster.
With every calculation, it becomes more familiar.
Crowe slowly realizes the mission was never about exploration.
It was about introduction. And once the archive is complete, humanity will no longer be observed from below.
It will be filed.