Series drift is usually blamed on the model. Read the board instead. The character was described from memory at every job, and memory seasons differently each time. “Honey-blonde hair in a low ponytail” in frame one becomes “blonde styled hair” by frame four, and the audience watches a stranger take her place. The repair is a kitchen habit: write her down once, on a menu card you paste rather than retype.
Five fixed lines, always in order
Age — a number, and in this room a mature one. Hair — colour, length and one habitual style. Build — two or three words. Face — one or two details that endure every crop. Signature — the ribbon, the mark, the detail that survives any light. Everything else belongs to the changing line: outfit, corner, hour, pendant light. Changing lines are meant to change. Board lines are not.
State the lines plainly and positively; adjectives are reinterpreted at every attempt, concrete descriptions survive. And version the card: when she is deliberately changed, print a new board, date it, and keep the old one, so an old set can be remade exactly as it was.
Working from the card
Pair the card with changing lines that share one setting and one light, generate at the standard 6-credit cost, and keep the best third. Spend on repairs, transfers and upscales only after the cull. When a frame returns off character, the cause is almost always on the card: a changing line contradicted a fixed line, or a line was too vague to hold her.
What a board cannot do
It cannot hold a character who was never decided. Decide her on paper first. The board is not where the imagination happens; it is where the imagination is served from, course after course.