The SS Arcadia vanished during a routine voyage. A strange, garbled emergency message was broadcast, but no trace of the ship, or of its crew, could be found. Sixty years later, its wreck has finally been discovered more than three hundred miles from its intended course. A small team are granted permission to dive to it. Their purpose is straightforward: explore the wreck, film everything, and, if possible, uncover how and why the supposedly unsinkable ship vanished. But the Arcadia has not yet had its fill of death, and the submerged halls hold more than simple mysteries. Trapped hundreds of feet beneath the surface, the dive team must fight for their lives in a place where even the smallest mistake turns deadly.