In television and film, a plot point is any incident, episode, or event that "hooks" into the action and spins it around into another direction. Noted screenwriting teacher Syd Field discusses plot points in his paradigm, popularized in his book Screenplay: The Foundations of Screenwriting. He proposes that a well-structured movie has two main plot points within a three-act structure. The first major plot point occurs 20 to 30 minutes into the film (assuming a standard 120-minute running time), and the second major one occurs 80 to 90 minutes into the film. Plot point I ends Act I and propels the story into Act II; likewise, plot point II ends Act II and propels the story into Act III.