Flesh and the Devil (1926)

Leo von Harden and Ulrich von Eltz have been best friends since childhood, when they even made a blood pact to stay so forever. They are currently bunkmates--Leo on the top bunk and Ulrich on the lower--in the German military, where they have five months left to serve. Leo has grown up to be the more irresponsible of the two, but Ulrich will still do whatever he can to cover up for Leo. Their friendship is ultimately be tested when, while the two are on furlough, Leo meets a mysterious, beautiful young woman he later learns is named Felicitas von Rhaden. Their meeting sets off a chain of events which will ultimately lead to a death and a love triangle between the three, but one of which Ulrich is unaware. Only Leo and Felicitas know the entire truth, but it's up to Leo in particular to decide what must be done to solve the problem they all face in light of Felicitas' unwillingness to do anything. Thrown into the mix is Ulrich's younger sister Hertha, who has always loved Leo herself, and Pastor Voss, who has known Leo since he was a boy and tries to be his voice of reason.