Propp Theory

The theory proposed by propp was that within every folk tale and narrative there is a maximum of 8 characters roles.

1. Hero/Protagonist
2. Villain/Antagonist
3. The Donor/Provider - gives a magical item that provides an advantage to the protagonist
4. The Helper
5. The Father Figure
6. The Dispatcher - sends the protagonist on a "mission"
7. The Princess
8. The False Hero

This can be instantly seen in numerous films for example:

The Lord of the Rings trilogy

Star Wars films

Star Trek films

James Bond films

The Matrix trilogy

And many more...