What do you call a movie that shows how a person became who he is known for? Let's take for example, Batman and Superman. Both of them became who they are through a series of meaningful events that made them become who they are today? What do you call a movie that shows those events so that people can understand who they were and why they became the people they are known for?
Here's an example sentence:
Elvis, the movie, is a ___ that shows how Elvis became the singer he is known for.