Abstract: An arrangement for presenting light-sensitive sheets, especially X-ray film sheets, to a treating machine, especially to a developing machine, includes a closure which is mounted at an inlet opening of a withdrawing station of the machine for movement between a retracted position in which it is spaced from the inlet opening, and an extended position in which it light-tightly closes the inlet opening. The cassette containing the sheets to be withdrawn at the withdrawing station is mounted on a carriage for joint movement through the inlet opening and forms a movable unit therewith. An engaging member engages the movable unit and causes the closure to move into its extended position during the movement of the unit in an initial path section, while an unlatching device unlatches the lid of the cassette during the movement of the unit in an intermediate path section, and a lid-opening device opens the lid of the cassette during the movement of the unit in path terminal path section.