The film begins with a voiceover describing the trench warfare situation of World War I up to 1916. In a château, General Georges Broulard, a member of the French General Staff, asks his subordinate, the ambitious General Mireau, to send his division on a suicide mission to take a well-defended German position called the "Anthill." Mireau initially refuses, citing the impossibility of success, but when Broulard mentions a potential promotion, Mireau quickly convinces himself the attack will succeed.