How to fix AI character drift: a four-point check and what each retake costs

Drift is not one problem

"My character looks different in this shot" usually means one of four things went wrong, and each has a different fix. Most guides tell you to lock a reference and audit every so often. That is right, but it skips the part you need on a deadline: which thing slipped, what you change, and what the retake costs.

We run recurring characters across episodes every week, and when a shot drifts we go through the same four checks in the same order. The order matters, because the first two are the cheapest to fix and the most common.

The four-point check

check	what drift looks like	usual cause	the fix
1. face	eyes, nose or jaw are a stranger's; age shifts	the reference is too small in frame, or only one angle was given	add a close-up angle to the references; reframe tighter
2. outfit	colour, logo or layers change	the outfit is not in the reference images, or the prompt describes it loosely	put the outfit in the pack and in the descriptor, word for word
3. build	taller, slimmer, different hands or proportions	a full-body shot with a face-only reference	add one full-body reference image
4. voice	pitch, pace or accent change in a voiced shot	the voice description changed between prompts	paste the same voice line unchanged into every prompt

Work through them in order, and fix only the one that slipped. Changing the reference pack, the prompt and the engine all at once means you will not know which change worked, and the next drift will catch you again.

Check 1: the face

Face drift is the most visible and the most common. Two causes cover almost every case we see.

The face is too small. In a wide or full-body shot, the face might fill a few percent of the frame. The engine is holding identity off very few pixels. Either reframe to a medium shot, or give the engine a close-up face image alongside the full-body one so it has something sharp to match.

One angle only. A single front-facing image holds well when the character faces camera. Turn them three-quarters and the engine guesses. Add a three-quarter left and a three-quarter right. Our character reference sheet guide shows the angles we use.

Engine matters here because of how many references each one takes:

engine	references per shot	what that means for the face
Seedance 2.5	up to 30 images	room for every angle and expression
Seedance 2.0 and 2.0 Fast	up to 9 images	three or four angles each for two characters
Kling O3 Pro	up to 5 elements	each element is a saved character with its own images
Veo 3.1 Fast	up to 3 images	best three angles of one character, nothing spare

If a two-character scene keeps drifting on Veo, the fix is often not a better prompt. It is moving the shot to an engine with more room.

Check 2: the outfit

Outfits drift when the engine is left to invent them. If your character wears a yellow raincoat with a red zip, and the reference images show only the face, every render chooses its own raincoat.

The fix has two halves. Put the outfit in the reference pack, as a full image of the character wearing it. Then write the outfit into the descriptor block, the fixed paragraph about the character that goes into every prompt, and never paraphrase it. "Yellow raincoat, red zip, hood down" in shot one and "rain jacket" in shot four is how you get two jackets. We keep the block short and literal; the descriptor block guide has the fields.

Check 3: the build

A character who is short and stocky in close-ups and tall in a full-body shot was usually referenced from the shoulders up. The engine had no evidence about the body, so it used a default. One full-body image in the pack fixes most of it. If the character has a defining body trait, a hunch, a limp, very long arms, name it in the descriptor too.

Check 4: the voice

Voice drift is easy to miss in the edit because you are watching, not listening. Play the episode with your eyes closed once. If the hero sounds older in shot five, the voice line in that prompt changed. On our voiced engines the voice comes from the prompt, so the fix is the same as for outfits: one voice line, pasted unchanged. We go deeper in our voice clone character guide.

What a retake costs

Once you know what to fix, you re-render one shot, not the episode. These are the credits our studio quotes for typical 5 to 8 second retakes, at 720p unless noted:

retake	Kling O3 Pro	Seedance 2.5	Seedance 2.0	Veo 3.1 Fast
5s, voiced	150	350	225	not served (4, 6 or 8 only)
5s, silent	120	350	225	not served
6s, voiced	180	420	270	180, or 240 with a reference
8s, voiced	240	560	360	240
8s, silent	192	560	360	160
8s, voiced, 480p draft	not served	280	176	not served

Two notes. Veo 3.1 Fast always renders 8 seconds when it is given a character reference, so a 6-second retake with a reference is quoted and billed at 8. And on Seedance, voiced and silent cost the same, so turning audio off does not save anything there.

At the Lite rate, 1,000 credits for $10, an 8-second voiced Kling retake is $2.40. That is the number to weigh against shipping a shot where the hero is slightly off.

A cheaper way to test a fix

When we are not sure a fix will work, we test it before paying for the final. For a Seedance shot, render the retake at 480p first: 8 seconds of Seedance 2.0 at 480p is 176 credits, against 360 at 720p. If the face holds at 480p, it holds at 720p. For a Kling shot, render silent at 24 credits a second instead of 30, check the face, then do the voiced final.

This is the one place we break the "change one thing" rule on purpose: lower resolution or silence does not change identity, so the test still tells you whether the reference fix worked.

When to stop retaking

If the same shot drifts three times after you have fixed the right point, the problem is usually the shot, not the character. Very fast motion, heavy shadow across the face, a back-to-camera turn, or a crowd that steals the engine's attention. Rewrite the shot: slow the move, bring the light round to the face, or split it into two shorter shots. Splitting is cheap, because the second half can often go on a cheaper engine. Our guide to splitting a long video into shots shows how we cut.

Our routine, in one list

• Build the pack once, with close-up, three-quarter angles and one full-body image.
• Keep one descriptor block and one voice line, and paste them unchanged.
• After each episode, scrub the shots side by side against episode one.
• When something slips, run the four checks in order and fix only that one.
• Test the fix at 480p or silent, then render the final.

It is the same routine whether you work by hand or in the studio, where every shot quotes its credits before it renders and a scene with more characters than the engine takes is refused rather than billed.

FAQ

Why does my AI character look different in every shot?

Video engines do not remember earlier renders, so each shot re-reads the references and prompt from scratch. Drift usually comes from a small face in frame, a single reference angle, an outfit missing from the references, or a description that changed between prompts. Fix the one that slipped.

How do I keep the same face in AI video?

Give the engine several angles of the face, including a close-up and two three-quarter views, and keep the face large enough in frame. On ReelDouble, Seedance 2.5 takes up to 30 reference images and Kling O3 Pro up to 5 saved characters per shot.

How much does it cost to re-render one AI video shot?

On ReelDouble an 8-second voiced retake is 240 credits on Kling O3 Pro or Veo 3.1 Fast, 360 on Seedance 2.0 and 560 on Seedance 2.5 at 720p. At the Lite rate of 1,000 credits for $10, the Kling retake is $2.40.

Why does my AI character's outfit keep changing?

The outfit is usually missing from the reference images or described loosely in the prompt. Add a full image of the character wearing it to the references, and paste the exact same outfit description into every prompt instead of rewording it.

Should I change the engine to fix character drift?

Only when the shot needs more references than the engine takes. Veo 3.1 Fast holds 3 reference images, so a two-character scene that drifts there often holds better on Seedance 2.5 or Kling O3 Pro. Otherwise fix the reference or the description first.