The beginning of the movie is basically what not do in a movie theaters. Don't record the movie, don't have your phone on and etc. Do not skip this part, it is very funny and also it ties in with the main story of the movie.
I really don't want to write anything else because I don't want to spoil anything and I think you should experience the movie yourself because it is amazing.
10/10 Highly recommend watching this movie and the Gintama series if you haven't watch it yet.
