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.
John Keefe, a gambler, shoots and kills Robert Barrington in an argument over a card game. Keefe steals Barrington's papers and forges a bill of sale to himself for Barrington's stable of race horses back east.
Movie mogul Thomas H. Ince may well have been the director of The Despoiler as indicated by the credits; but since Ince was known far and wide as a glory-hogger, it's also possible that one of his talented lieutenants wielded the megaphone.