Purun can't blow big bubbles, and the show doesn't pretend that doesn't matter. What hits is watching a character made small by comparison find that her particular smallness is exactly what saves everyone else. The movie knows the difference between not being the best and not mattering.

Anpanman's friends head out to watch a bubble show put on by Shabondama-hime and her Shabondama Girls, who blow beautiful bubbles by playing their flutes. One of the girls, Purun, cannot make big bubbles however hard she practices, and she feels she does not measure up. While she sets off to get back her lost flute, which Creampanda has found and is bringing to her, Baikinman seizes Shabondama-hime's castle and steals the flutes, using them to make wicked bubbles. With Anpanman's help, Purun has to recognize her own value and save the day in this comic fantasy film.