Mabel's Busy Day is a quick story of a vendor at a sporting event and the troubles that she encounters throughout her day. Chaplin actually plays the part of a more well-to-do individual, but he is still very recognizable, with the traditional look that Chaplin always seems to have. Also, he still manages to get into plenty of the high-paced and very amusing scuffles that are almost as much of a trademark in his films as that outfit.

What really makes this film unique is that Charlie actually plays the part of the antagonist. When the server girl - the vendor who the film is about - gets picked on by hordes of people, Charlie comes to the rescue, but he ends up hitting on her and then getting turned down. Not only did he not get the girl, but he also ends up stealing all of her products (which happen to be sausages) and handing them out to all of the people who are nearby. This is totally uncharacteristic, but it does not take away from the quality of the comedy delivered by this short film. The fight sequences, although dated very badly because of sheer physical deterioration, were particularly entertaining and amusing.