This article proposes a stylistic study of Piotr Rawicz’s (1919-1982) Sang du ciel [Blood from the sky] (1961) by examining the recurrent use of irony in narratives of the genocide. The analysis of a scene describing the massacre of Jewish children makes it possible to situate irony within the more general context of a rhetoric of the unspeakable that is specific to narratives about the genocide: writings on "doing as if" one could recount that over there aim to suspend the readability of the represented reality while blurring the conventions of the already-said and already-thought by a new modulation of the aesthetic and pathetic interferences of literary discourse. The discussion seeks to demonstrate how the use of figures by analogy like comparison or metaphor produces an effect of an imaginary void through a deconstruction of tropic structure, whereas irony, on the contrary, produces an effect of the unspeakable through an excess of readability.