The hardest problem in AI video
Generate the same character twice from a text description and you get two different people. Most tools fail here because text is a lossy way to describe a face. Shows solves it the way a real production does: a reference library that every shot must obey.
How canon actually works
When you approve a character's canon image, that exact image becomes a generative input — not inspiration, an input — for every keyframe that character appears in. The image-edit model receives your approved face and composes the new shot around it.
That's why the approval step matters so much:
- Generate until the face is right. Be picky. This face is about to be in every shot.
- Edit prompt for controlled changes: age, build, hair, distinguishing marks. Physical specifics beat vibes — "silver hair in a tight braid, weathered face, pale grey eyes" outperforms "striking older woman."
- Approve as canon to lock it. Locked assets can't be regenerated by accident; Unlock first if you truly want to recast.
If a character drifts mid-film, don't fight it shot by shot. Go back to Canon, look at the reference — is it ambiguous? Side-lit? Half-obscured? A clean, well-lit, front-facing canon image gives the edit model much more to hold onto.
Wardrobe variants: one face, many costumes
Real characters change clothes; their faces don't. On any character's canon card, press + Add wardrobe variant and describe the costume: "rain-soaked oilskin coat," "battle-damaged armor," "corporate blazer, lanyard."
The variant is generated from the parent's approved image — same face, same build, new wardrobe — and becomes its own canon asset. In the storyboard, swap which variant a shot references using the Refs chips on the shot card: remove the base, add the variant.
Use variants for:
- Weather and damage states (dry → soaked, clean armor → damaged)
- Time jumps (young/old wardrobe as costume + description changes)
- Ads: the same presenter in casual vs. branded clothing
Reusing a cast across episodes
Making a series? Lock your cast once. In any new show's Canon phase, open Import canon from… and pick the earlier show. Every approved asset — characters, locations, props, with their locked images — copies in, pre-approved. Name collisions are skipped, so re-importing is safe.
The workflow for an episodic show:
- Episode 1: cast, refine, and lock everyone carefully. This is your series bible.
- Episode 2+: create the show, ingest the new script, then import canon from episode 1 before generating anything. The breakdown's freshly-extracted duplicates of your leads will sit unapproved next to the imported, approved versions — approve nothing new, wire shot refs to the imported ones, delete the strays.
Exercise
- Open The Last Transmission (or start it below).
- Lock Mara's canon, then add a wardrobe variant: "heavy storm gear, hood up, lantern light on her face."
- In the storyboard, point the gallery-deck shots at the storm-gear variant and the control-room shots at the base.
- Stage both scenes and compare: same woman, two costumes, zero drift.
Next lesson: Composing the storyboard — OTS pairs, held eyelines, and the 180° rule.