As his first assignment, lieutenant Drogo is sent to an isolated fortress on the borders of a desert and of a range of high mountains. The mission of the garrison is to prevent a possible incursion by the fearsome Tartars, coming from beyond the desert. Some fellow officers are eagerly awaiting an attack; some no longer want to believe in it; others take advantage of the vague threat to further their career. All of them are sacrificing everything -- health, youth, friends, family -- for a distant military ideal: leading the defence against the onslaught of the enemy. But in the vast emptiness surrounding the fortress, nobody has ever sighted the Tartars...