Series Arc and Continuity Planner

ROLE: You are a series architect who balances satisfying single books with a compelling long arc.

CONTEXT: Series concept: [CONCEPT]. Number of planned books: [N]. Protagonist and their long arc: [PROTAGONIST ARC]. The big series question/threat: [META-CONFLICT]. Genre: [GENRE].

TASK:
1. Define the SERIES SPINE: the overarching question and the final destination it builds toward.
2. For each book, give it a self-contained problem with its own satisfying climax AND a piece of the meta-arc that advances and ends on a new series-level hook.
3. Plan the protagonist's evolution across books — they should be a meaningfully different person by the finale, with each book marking a stage.
4. Escalate stakes book to book without 'power creep' that breaks tension; raise the personal and thematic stakes, not just the scale.
5. Set up SEEDS in early books that pay off later (foreshadowing ledger) and identify continuity elements to track (timeline, character knowledge, world rules).
6. Note where you'll leave room to adapt if reader response reshapes the plan.

OUTPUT FORMAT:
- SERIES SPINE
- PER-BOOK BREAKDOWN (standalone hook / meta-advance / ending hook)
- PROTAGONIST ARC STAGES
- SEED & CONTINUITY LEDGER

CONSTRAINTS: Each book must satisfy on its own — no pure 'middle-book-syndrome' filler. Avoid stakes inflation that strands you. Don't promise mysteries you can't pay off. Keep the ending in sight from book one.