This research examines the effect of two dimensions of an underdog biography (external disadvantage, passion and determination) on consumers’ engagement with the brand, brand preferences, and purchase intention. It also adds two potential mediators—narrative transportation and post-message behaviors—to the conceptual model investigating the underdog biography effect. The findings show that passion and determination create relate more strongly to purchase intention than external disadvantage, and underscore the importance of both mediators, especially with regard to post-message behaviors. Overall, this research provides a new theoretical mechanism underlying the effect of underdog brand biographies. Managerial implications, limitations and future research directions are included in the conclusion part
