One of the joys of an old folder like my Nettar 510 is its super-simple double exposure function. With no lockout to stop you, you can continue to shoot as many exposures as you like on a single frame. Sometimes for artistic or experimental reasons, more often, as in this case, accidentally. The drill has to be shoot then wind. Forgetting the drill gives results like this. Shooting quickly in fading light, forgot to wind the film. Ho hum...