The dynamics of communications powered by the Internet, specifically from the increased use of social media, has led marketers to find creative channels to engage with the customers. One of the recent channels, "branded entertainment", is becoming familiar as an advertising strategy in which the content presented is a marketing tool for the advertising of certain brands. The current study examined the case of a branded-entertainment channel and the mechanism of the advertising instrument that leads to purchase intention. The specific purpose of this research is to investigate whether there is evidence of the role of narrative transportation and the fantasy proneness leading towards purchase of the brand advertised. To arrive at the conclusion, the study using web series sponsored by an artificial sweetener brand and employs a quantitative survey to question the audience. The findings contribute toward the understanding of how consumers respond to branded entertainment via video-sharing platforms. It is indicated that the stories presented in the web series can stimulate the audience to fantasize. Thus, the advertising message conveyed through narrative persuasion can form a favorable attitude toward the brand, which leads to intention to purchase. Practical elements are identified along with limitations and future research suggestions.