A group of divers discovers portions of the long-lost WWII patrol ship USS Eagle PE-56 off the coast of Maine.

After finding the bow of the Eagle 56 at the bottom of the Atlantic, explorers search for the rest of the warship to uncover why it sank.

After four years and countless dead ends, a team of civilian investigators has found pieces of the sunken Eagle 56, the Holy Grail of New England shipwrecks. They want to reveal their discoveries to both the Navy and the families of the warship's crew, but their case is not yet complete.