La Lettre is a narrative game where ten obligatory situations transform three characters — for real. It is also the first proof of a Controlled Generative Drama Engine: an AI that can choose the path, never the dramatic destination.
One night in 1919 at Rosalie's. Initial state → freedom of action → threshold → irreversible transformation. The player can reach the threshold in several ways; once it is crossed, something has genuinely changed.
The Controlled Generative Drama Engine: the closer an element is to the dramatic core, the less freedom the AI has. The canon, the threshold and the final line remain authorial points.
An AI-native pipeline backed by specialised studios and laboratories, from playable prototype to scale-up, and by a stage-floor method inherited from the theatre.
The game: situated, embodied, finished. It gives the technology meaning and proof. It is the vertical slice and the artistic demonstration.
Controlled generative drama: a reusable asset beyond the game. La Lettre is its first use case, not necessarily the principal asset.