This is what your initially act, indeed, your initial 10 pages should do. This act has many functions. It establishes who your leading characters are, the setting, the time period, the theme, genre and tone. It is within this act that we meet the protagonist as well as the antagonist.
In some films we can not meet the antagonist straight, but we are at smallest introduced for them, with hints at ultimate an revelation, including is frequently the case in mysteries. Although we might not see them yet, we are created perfectly aware of their presence as well as the bad, often devastating impact they might wear alternative characters in the story.
It equally establishes the premise of the story: a saloon owner is surprised to find the girl he likes walk into his lifetime during World War II. Casablanca. A big shark menaces a beach resort town at the starting of the summer tourist season. Jaws. A young fighter pilot should save a kidnapped princess and destroy an wicked empire. Star Wars.
Your initially act should actually grab the Hollywood exec by the throat in the initial 10 pages or they can stop reading and move forward to the upcoming script in the pile.
The initial act of the script is usually longer than 10 pages, but that is all time and area you need to persuade somebody to continue reading.
Most screenwriting teachers state that the initial act ought to be about one-fourth of the screenplay. But countless initial works are less. All initial works end with all the inciting incident, that is an event that arises that either encourages or forces the protagonist to take their path in a fresh direction.