Develop a film idea · Part 2 of 6
Character Bibles, Motivations & Relationships
Decide who your characters are, what they want, and how they collide.
Take the locked logline and answer four things for each principal: what they want, what they need, the lie they live by, and what they use the other people for. A character bible is that document — not a biography, not a casting sheet. If you cannot say want / need / lie in a few lines, you are still describing a type.
What is a character bible?
A bible is the smallest set of facts that would make this person behave differently from anyone else in the same plot.
- Want — the visible goal (what they would say they are after)
- Need — the change they resist (what the movie is actually about)
- Lie — the sentence they tell themselves so they do not have to change
- Relationships — who they complete, threaten, or use
Backstory only stays if it explains one of those four. Favorite food, star sign, and childhood trivia do not.
Michael Corleone — The Godfather
Want: stay out of the family and keep his own life intact.
Need: become the person who can protect that family.
Lie: “That’s my family, Kay. It’s not me.”
Relationships: Vito is the man he will not be; Sonny is the temper he refuses; Kay is the proof he is clean; the other families are the reason the lie collapses.
Luke Skywalker — A New Hope
Want: get off the farm and into the fight.
Need: commit to something larger than his restlessness.
Lie: “There’s nothing for me here” — as if leaving were the same as choosing.
Relationships: Uncle Owen is the life that keeps him small; Obi-Wan is the call; Leia is the mission; Vader is the cost he cannot see yet.
What to start with
- The locked logline from the last lesson
- Who has the problem (protagonist)
- Who benefits if they fail (antagonist)
- One person who makes the protagonist worse, and one who makes them tell the truth
- Any hard limits you already set (period, rating, arena)
Do not start with a face, a wardrobe, or a “vibe.” Those come after the want and the lie are stable. If you load a Claude Project later, feed it pages you wrote so the voice stays yours. Chikai
Want, need, lie
Write three lines per principal. Force a collision.
- If they get the want and never face the need, you have a plot, not a character.
- If the need is “learn to love themselves,” you have a poster, not a person. Make the need specific and expensive.
- The lie should be something they would actually say. If it only works as an essay, it is not in their mouth.
Michael’s want and need cannot both win. That is the movie. Luke’s want can win in two hours; the need is only started. Both are valid — but you have to know which one you are writing.
Map relationships before more plot
A relationship is not “allies” or “romance.” It is a use.
For each pair, write one sentence:
A uses B for ___ . B uses A for ___ .
If both uses are the same, one of them is furniture.
Typical useful roles:
- The person who believes the lie
- The person who will not
- The person who wants the same goal and will burn the hero to get it
- The person the hero cannot afford to become
Do this before you add set pieces. Scenes will start appearing from the uses.
Life before the movie starts
The character has already settled. The logline is the interruption.
Write one paragraph: how they spend a Tuesday, what they have agreed to tolerate, what would have to happen before they would leave that life. That paragraph is the “before.” Everything after FADE IN should make that Tuesday impossible. Myers
Worked swap (keep the engine, change the person)
Base logline: After a pop star’s bodyguard witnesses a murder, he must keep her alive long enough to testify, or the syndicate erases them both.
Bodyguard as lead
- Want: get her to the grand jury and get back to being invisible.
- Need: admit he already failed someone he was paid to protect.
- Lie: “This is a job. I don’t get attached.”
- Uses Uses her for a clean exit. She uses him for a wall.
Pop star as lead (same plot, different movie)
- Want: keep the tour on the rails so the career does not stall.
- Need: stop treating other people’s danger as weather.
- Lie: “If I stay famous enough, nothing can touch me.”
- Uses Uses him for cover. He uses her for a last chance to do the job right.
Point at what changed: who has the want. If you also changed the syndicate, the tour, and the ending, you started a new pile.
Kill test
For each principal, make the model argue against the bible:
- What existing character is this already?
- Can you swap their name with the antagonist’s and the page still works? Then they are not specific.
- If we give them the want on page 10, is there still a movie?
- What would they never say — and are you about to have them say it in scene two?
If you cannot defend want / need / lie out loud without the plot, the person is not locked.
Using AI as a writing partner
Start from the locked logline. Develop one person at a time. Do not let the model write dialogue or scenes yet.
Paste into your AI chat
Treat the model like an operator: persona, constraints, structured output. Not “give me character ideas.” Nainsi
When the bible is stable, you can compress each person into a short DNA block for later image work (face, silhouette, wardrobe, accent). Accent belongs in that block or you get a generic American. That is production. It is not this lesson. Jay