Beware!

Kaiser Wilhelm, on trial before an international commission, defends himself by saying he was serving God and following his ancestors. One of these, William the Fat, provokes his son Frederick through terror into becoming the militarist leader later known as Frederick the Great. The barbarity of Attila the Hun is shown to be similar to that of the Kaiser. A German officer kills a French woman and her son, and rapes her daughter. Later, the daughter, who has become a Red Cross nurse, treats the officer and stops him from suicide. A deranged British soldier, tells of his POW experiences with an American and Frenchman, the Frenchman being knifed by a wounded German soldier he was helping. Documents are brought into evidence supporting the testimony. The German officer warns the court to beware of still-existing militaristic Prussianism. The Kaiser finally shows his true colors by yelling that God demands the destruction of all that oppose him.