Mabel has just gotten engaged during a housewarming party of which her mother is the hostess. When an annoying party guest persuades Mabel to dance with him, Mabel hurries through the dance and then goes to look for her fiancé, only to discover him caressing another woman. Her fiancé finds not only Mabel, but also her mother, very displeased, and not inclined to believe his explanation.

Frequent comedy co-stars Fatty Arbuckle and Mabel Normand take viewers on a tour of the 1915 Panama-Pacific Exposition in San Francisco. Attractions shown include the U.S. Battleship "Oregon", the Australian convict ship "Success" (complete with such punishment devices as a flogging rack and a spiked Iron Maiden), the world's tallest flagpole (251 feet), the Court of Abundance, the Court of the Universe (with sunken garden) and the Tower of Jewels. Fatty and Mabel also visit Frisco's still-under-construction City Hall, accompanied by Frisco's then-Mayor James Rolph Jr. Also appearing in the film is opera star Ernestine Schumann-Heink.

Mabel is pursued by her boss, despite being engaged to his son, in this gender-bending comedy of errors and mistaken identities.