Flaw is a powerful examination of the way in which a costume or uniform can confer a certain power or status, regardless of the competency or the morality of the wearer. The novel begins with the description of a tailor who is employed to make costumes for the story that follows. He is not adequately compensated for his work; as a result, he becomes indifferent and embittered, and most of the costumes he creates are cheaply made and fit the wearer poorly.

Magdalena Tulli's brilliant psychological novel unfolds slowly at first, as she details the lives of several characters key to the story, including a student, a notary and his family, a maid employed by the notary, a policeman, and a waiter. Their lives are quiet, unsatisfying, and limited to the town square in an unnamed modern eastern European city in which they reside. Word of a severe financial and political crisis suddenly comes to the notary by telephone, and the other citizens quickly get the news from the radio. A family from a distant town in the midst of the crisis is brought to the square by streetcar and is soon followed by other refugees with their belongings. Their manner and dress offend and displease the residents; as more of the foreigners pour in, the policeman confines them to the square. The student modifies his clothing to resemble a uniform and assumes command of an "order guard" consisting mainly of grammar school students, who mete out punishment to the refugees indiscriminately. When a group of airmen who have mistakenly come to the town in search of an air base are rescued by helicopter, their general leaves his greatcoat behind in a café; the waiter, who has been beaten and humiliated in the past, dons the greatcoat and assumes command. He is eager for revenge and seeks to inflict it upon the foreigners, as he comes up with a plan to remove them from the town—permanently.

The lesson of this narrative, whose events bear close resemblance to those occurring in political upheavals in 20th-century Europe, can be applied broadly to any situation in which an individual influences others on the basis of a uniform. The narrative requires the reader's close attention because of the shifting monologues and the interplay of the characters with the uniforms they wear. However, this is not an overly difficult read, and the careful reader will be rewarded by the effort.