But thirty seconds later, the radar showed something else. Fourteen dots. Then nineteen. The signal was multiplying.

As if something deep in the Rockall Trough—something that had waited for a very long time—was learning how to answer.

Four rising tones, a pause, and then a single low thrum. Over and over.

The MS Northern Eagle arrived seventeen minutes later. They found one life raft, adrift and empty. They found the Arcadia’s bridge, half-submerged, the command console shattered. They found no bodies. No oil slick. No debris field.