Screenwriters, please remember this: it's not how big the action that matters, it's how big the stakes.
The most powerful scene is the one that raises the potential for success or failure -- bigger rewards, worse odds. When it comes to what is happening in the scene, you can have planets collide or you can have two people talking. The two people talking will always be more powerful. That's how it is with humans. You can claim the survival of the planet is at stake and it won't interest audiences. But let us come to know just one person on that planet very well, and the suspense will be unbearable.
It's not how big the action that matters, it's how big the stakes.