A father and son team of divers and explorers, Mike and Warren Fletcher, travel to the remote Caribbean island of Saba to investigate a mysterious, modern steel-hulled shipwreck resting on the ocean floor. With no official records of the ship's name, origin, or sinking, the Fletchers embark on a dangerous, multi-stage mission to identify the vessel and uncover the truth behind its final voyage. As they piece together clues from the wreckage, they begin to suspect that the ship may have been involved in a clandestine criminal enterprise, potentially involving drug smuggling, which could explain why it vanished without a trace.