Abstract: A light sensitive, heat developable film is stored in a cassette which includes a sliding film carrier bracket for transporting the film into and out of the cassette housing. Each cassette housing encloses a supply spool, a take-up spool, the light sensitive film, the film carrier bracket mechanism and a drive means for propelling the film carrier bracket in and out of the cassette housing. A door is slidably attached to the front of the housing to shield the film from ambient light when the cassette is not in use. When the cassette is placed into a recording machine the supply and take-up spools are engaged by motors capable of driving the spools forward or backward. At the beginning of operation an internal drive motor propels the film carrier bracket into contact with the inside of the door which releases an internal door lock. An external lead screw then withdraws the door upwardly.