Photography is a practice that has never ceased to evolve and transform with technical inventions and with the internal reshuffles of the artistic field with which it maintains close relations. The much-debated question of a specificity, even an "essence", of this medium is set aside, in order to focus instead on everything that makes it uncertain, elusive and paradoxical. The photographic (or partially photographic) works discussed here are, most of the time, amalgams in which documentary and narrative capacities, what has been called their "inner narrative", mingle. But at the same time, and quite the opposite, they seem worked by dissociative forces, a tendency to heterogeneity. The photographic object never stops mutating, playing with its paradoxes and its limits. The presence of photography (of "the photographic" would perhaps be more accurate) introduces chains of disturbances, which interviews and essays ("case studies") try to account for.