Pennsylvania, 1956. Frank Sheeran, a war veteran of Irish origin who works as a truck driver, accidentally meets mobster Russell Bufalino. Once Frank becomes his trusted man, Bufalino sends him to Chicago with the task of helping Jimmy Hoffa, a powerful union leader related to organized crime, with whom Frank will maintain a close friendship for nearly twenty years.
Deep in the Mariana Sea Trench, a corporate underwater mining complex has been built - an industrial Atlantis. When an accident in a dry-dock chamber kills several miners an investigator is sent to find the cause and immediately finds out that it was not an accident. He becomes caught in the middle of a deadly conflict between the miners and the corporation, and fights to stay alive and uncover the truth.