Film Language Tag: inciting incident
The plot point (or turning point) that disturbs the balance in place at the start of the story and gives the central character a goal, desire, mission, unfulfilled need, or problem. The rest of the story deals with how the central character achieves this goal, satisfies this desire, etc. In the traditional three-act structure, this is often the plot point that moves the story from Act I to Act II. [Also known as disruption of equilibrium]