This book explores why word of mouth is the most important determinant of a movie's success. Beginning with a discussion of the enduring appeal of movies, and why the box office has survived the disruption of television and will likely survive the disruption of streaming services, Owen Eagan goes on to discuss the unpredictable nature of movies and ways to mitigate their risk. His astute analysis sheds light on the role of film festivals, film critics, Oscar campaigns, and word of mouth in influencing a film's success. Eagan concludes with a summary of why word of mouth is the most influential among all the variables that affect a film's outcome.  Expertly synthesizing quantitative analyses of box office data with illuminating insights from industry experts, this concise and engaging book presents findings with important implications for scholars, industry insiders and marketing professionals alike.