All of the answers for where we need to go in your story already exist in the initial pages of your screenplay. The structure of your movie can grow organically simply by looking at the things that exist in your story, and saying, “If this is true, what else must also be true? And if this is true, what else must also be true? And if this is true, what else must also be true?”

In this context, by the time we make it to the end of the movie, in some way, everything possible must happen…

Now, just a warning, there are major spoilers ahead.

What’s wonderful about 10 Cloverfield Lane is that we never know exactly what is true and what is not. In fact, we’re dropped directly into the experience of the main character.