Narrative perspective from which we experience the story — whose knowledge and emotions we share, not who narrates. Determines what the audience sees and conceals.
Focalization determines what information the viewer receives at what moment—and what remains withheld. It's not about the voice that narrates, but about a character's knowledge and perspective through which we perceive the film's world. On set and in the edit, this is crucial: a scene plays out completely differently if we only know what the main character knows, compared to if we have already revealed the secret to the audience.
In practice, we distinguish three degrees. With zero focalization, we know more than any character—the classic omniscient narrator. We see the intrigue unfolding while the protagonist suspects nothing. This allows for dramatic irony and suspense through knowledge. With internal focalization, we only see what the character sees and knows. This is the most restrictive form: we understand the world through their eyes, their thoughts, their confusion. Subjective camera perspective, point-of-view shots, and sound design support this. Finally, with external focalization, we know less than the characters—we observe them from the outside, without access to their thoughts or motives. This creates mystery and distance.
Practically, this means: if you're editing a thriller and in Scene A you use the heroine's internal focalization, you just see the murderer at the window—but she doesn't. Suspense! If you then switch to external focalization in Scene B, you suddenly lose this privileged information. The viewer is left in the dark like the other characters. This is a dramatic tool, not just a theoretical exercise. With focalization, you control the pace of revelation. You can sow confusion, create complicity, or prepare for surprise.
The shift between focalization levels must be deliberate—not accidental. Internal focalization works excellently in horror films because we share the character's fear. In a detective mystery, you need external focalization to provide fair clues without revealing too much. Remember: focalization is not the same as camera perspective (see: Point of View), but rather a narrative limitation of knowledge conveyed through all cinematic means—editing, sound, even color grading can reinforce or break it.