To the Germans he is Hauptmann Augustus Lang, a special agent of the Gestapo SS. To the Allied High Command he is Captain Gus Lang of the Ninety-Second Infantry, Code Name: Emerald.
In the spring of 1944, the Nazis capture an United States Army officer who knows vital information about the imminent Allied invasion of Europe. Now, one man--Captain Gus Lang (Ed Harris)--parachutes behind enemy lines with the mission to prevent the Germans learning about D-Day ... by whatever means necessary.