This publication shows a deep gaze about the most important photography book from the 20^th century in Portugal, whose double authorship belongs to the architects Victor Palla (1922-2006) and Costa Martins (1922-1996). A 1959 book that recorded three years of the architects’ wanderings through the streets of Lisbon, depicting it and its inhabitants, revealing a hidden city, simultaneously a sad and a joyful one.