A story arc where the character already holds the truth and instead changes the world around them.
Don't let the name fool you - a flat character arc has nothing to do with flat or boring characters. It describes a protagonist who already understands the central truth of the story from the beginning. Instead of undergoing internal transformation, this character acts as a catalyst, challenging the broken world or flawed people around them until something gives. The change happens externally - in other characters, in institutions, in the status quo - while the protagonist's core beliefs hold steady under enormous pressure.
Flat arcs are everywhere in fiction, and they work brilliantly when your story is about standing firm in your convictions. Think of any time a character walks into a messed-up situation and simply refuses to bend. If your story is more about changing the world than changing yourself, a flat arc might be exactly what you need. Recognizing this arc type also saves you from forcing unnecessary internal change on characters who are strongest when they hold their ground.
Atticus Finch's moral convictions never waver - he changes how Scout and the reader see justice and decency in their town.
Diana's belief in love and justice remains constant while she transforms the cynical soldiers around her and confronts the truth about humanity.
Paddington's kindness is so unshakeable that he literally reforms an entire prison population through politeness and marmalade sandwiches.
Steve Rogers' moral compass stays fixed while he exposes the corruption within the institution he trusted most.
A flat arc character still faces enormous external challenges and pressure. The drama comes from watching them hold their ground when everything pushes against them.
Even flat arc characters should be tested and tempted. The tension comes from moments where abandoning their truth would be so much easier - and they choose not to.
If nothing changes externally, you don't have a flat arc - you just have a static character in a static world. Track the ripple effects of your character's steadfastness.
Write a scene where your character walks into a situation where everyone else accepts something your character finds deeply wrong. Have them refuse to go along - not through a dramatic speech, but through a small, quiet action. Then show how at least one other character in the scene is unsettled or quietly inspired by what they witnessed.