A stripped-down visual sonata, in which elements of Lange's habitual cinematic universe (wall, wasteland, city square, cars ...) are captured by a camera more 'documentary' than demiurgic (as opposed to the transformation of energy and vision to be found in his later films).The filmic process used is, however, no less rigorous. Urban prison transportation was filmed from the inside of a moving vehicle and is composed of lateral travelling shots, which move consistently forward, while swinging from left to right with a varying degree of acceleration. There is no double-exposure or editing-in-camera; the background consists of walls, parks, wastegrounds, stations and platforms. These compositions in movement display various degrees of depth of field; speed decreases as we retreat, diffracted by the systematic presence of the grills and bars separating us from more distant motifs.