The new ending was a seismic shift, a secret they guarded more fiercely than any budget figure. While the visual effects team, under David Chen’s loyal supervision, began the frantic work of creating the “shattering light” sequence, the marketing machine had to begin its roll-out. They were behind schedule, and the industry buzz, once white-hot, was threatening to cool.

The strategy, devised in a tense meeting with the Meridian Pictures marketing team, was one of ...