It's a beautiful movie and I highly recommend watching it.
The movie describes a life of a side actor and his impact on movie making and how they are perceived by the audience. It shows how crucial they are for those film but despite whatever efforts they make, they will be forgotten and overshadowed by the lead characters.
(SPOILER AHEAD)
This is very clear when during the final part of the movie the movie the principal asks our lead for his name as she only recognizes as one of the faces in the movies but never cared enough to learn even his name.
Also when the bigger star arrives people forget the one who had been giving his blood and sweat into entertaining them.