World War One caused greater destruction and involved more countries than any other war except WWII. An assassin's bullet set off the war, and a system of military agreements brought the main European powers into the fight. Both sides expected a quick victory, but the war lasted four years and took the lives of almost 10 million men. Extreme patriotism gave men a cause to die for and propaganda raised support for the war while making the enemy seem villainous. This fascinating 2-part documentary program chronicles the major events of this devastating period in the world's history through insightful narration and compelling archival footage and photographs.