In just over a two-year span as the 1970s marched on toward the 1980s, John Travolta starred in three cultural touchstone movies: "Saturday Night Fever" (released on December 12, 1977), "Grease" (released on June 16, 1978), and "Urban Cowboy" (released on June 6, 1980). This episode examines the cultural significance of those films, the music in them, and how much Travolta himself had to do with the popularity of the movies.