Notable as Charlie Chaplin's first female impersonation film, the half-reel A Busy Day is another of the Keystone shorts in which a film crew was dispatched to improvise a comedy at the site of a public event, in this case a parade celebrating the opening of a new harbor in San Pedro, California. Chaplin plays a shrewish wife, attending the event with her philandering husband, Mack Swain. Mack takes up with a young woman at the parade and his wife follows him around trying to catch them in the act. In the process, "she" gets involved with a film crew trying to record the event, getting in the way of the camera as Chaplin's Tramp had done in the earlier Kid Auto Races. In this case, the director who manhandles the obstreperous wife is Keystone boss Mack Sennett. The jealous wife also engages in some humorous dancing as she listens to the band play and tussles with a cop who earlier had tried to get her away from the movie camera. Eventually she catches up to Mack and his paramour, and when she confronts and attacks them, she is thrown off a pier into the ocean