The girl who summons the stars is an okay movie in the irregular at magic high school franchise. It is not standalone and should be watched after the second season so you're familiar with the characters. Its story isn't the best and it's not immediately clear where the plot fits in relation to the rest of the anime. The things that are happening are explained but they seem extreme and chaotic. There isn't any significant character development in this movie either. The main reasons to watch the movie are fanservice and cool action scenes. The art is quite nice and the sound is okay. Overallit can be a fun movie to watch and if you liked the first two seasons of the anime chances are you'll like this movie as well. If you haven't watched the anime, please watch that before the movie.