How strong and enduring can the impact war causes on a human being be? How does it influence family and friendship ties? How does it affect the body, mind and spirit of veterans? These are some of the questions approached in this documentary, whose background is the trajectory of the men from the III Batalhão do 6º Regimento de Infantaria [3rd Battalion of the 6th Infantry Regiment] - "Navalha" ["Switchblade"] -, of the Força Expedicionária Brasileira (FEB) [Brazilian Expeditionary Force], as well as the battles they fought in the Gothic Line, raised by the Axis armies in Italy, during World War II. The guiding thread of the narrative follows the statements of twenty interviewees, chosen among former combatants and historians. Based on the eyewitness account of soldiers who lived the horror of war, the work dives into the Brazilian soul, values, beliefs, singularities, virtues and flaws in the face of the other peoples involved in the conflict. Filled with never before seen photos and footage depicting the Brazilian participation in the conflict obtained from national and foreign archives, the production includes one decade of research and interviews conducted with FEB veterans in different Brazilian cities. All of this was done without using a single cent coming from government or private funding. "Navalha" is also a story of overcoming of humble young people - most of them coming from farms in the hinterland of Brazil -, who were suddenly put to the test in an arena where the major world powers were testing their strength against one another: the battlefield. The documentary recovers the epic trajectory of men who responded to the call of duty, in a decisive moment for the fate of Mankind, by writing a page in history that Brazilians can truly be proud of.