Off the coast of Cornwall a wartime maritime convoy heads for France in 1944. Suddenly an explosion rocks American merchant freighter, the Ezra Weston. The Canadian corvette, Regina, turns back to help. Within minutes, she too is blown apart, taking thirty men to their deaths. Did rogue mines strike both ships or was there something more sinister lurking below the surface targeting them? Advances in underwater technology now allow experts to revisit their watery graves and unlock the controversial events of that night for the first time, unmasking the guilty, and the gallant.