This is the Army

In this Oscar-winning film, a musical is put on for the servicemen fighting in World War I and a soldier who performed in the show heads off to war, where he is wounded and is forced to give up his career as a performer and become a producer. When World War II breaks out, the cast of the original musical decide to stage a new version for the servicemen heading off to fight. The producer's son, soon to be heading off to battle, is torn by his love for his fiancée and his call to duty so he refuses to marry her until after the war.