She took a tentative sip from her mug, the bitter liquid doing little to chase away the lingering fatigue. The image of that ancient, enigmatic structure the ROV had captured before the feed went dark was etched vividly in her mind. The intricate symbols, the imposing architecture it was unlike anything she had ever encountered in her years of oceanographic exploration.

"What are you?" she whispered to the sea, as if expecting an answer from the depths below.