Over eighty years after the end of World War II, Slovenia still conceals hundreds of pits and mass graves that serve as silent witnesses to the mass executions carried out by Yugoslav army units during the post-war period. The book "Concealed Graves of Croats in Slovenia" by Slovene historian Mitja Ferenc and archaeologist Uroš Košir offers one of the most comprehensive scientific accounts of these events known as the Bleiburg tragedy. Ante Žužul, in the book's preface, explicitly describes these acts as ‘genocide against Croats,’ emphasizing that the scale, method, and purpose of the post-war killings transcend all logic of revenge, entering into the realm of the planned destruction of a national group during peacetime.

For decades, these gravesites were guarded not only by concrete, soil, and forest but also by ‘guards of death’ – institutions, agencies, and individuals whose task was to ensure that the truth never sees the light of day. Based on extensive research, the book seeks to bring forth the hidden narratives of these atrocities, digging deep into the historical context that allowed such events to occur undetected and unreported for so long. The authors reveal the systematic nature of these executions and the long-standing denialism that has surrounded them, illuminating the persistent shadows that hang over Croatian-Slovenian relations and the collaborative responsibility shared by various authorities in denying this historical truth.