It is 1945 and Hitler is dead. Ben and Katherine are supposed to be together, happy. Instead, Ben fights the war in the Pacific with the reckless heroism of one who believes his fiancee killed in action. Yet, Katherine lives, undercover aboard a submarine about to arrive at the Third Reich's last bastion. Ben tries to move on, until the Navy receives a message. In Antarctica, the Nazis are plotting their return, powered by strange and foreboding technology.