Kaijyu Mono is a film that puts a comedic lens on the typical Japanese monster film. When he is injected with Setup X, Nitta transforms into a muscular giant, who is able to fight off Mono with a variety of wrestling moves. The grants Nitta instant celebrity, as well attracting the attention of foreign spies. However, Nitta quickly learns that defeating Mono for good might not exactly be an easy task.
Kaijyu Mono is an incredibly entertaining film, which has a lot of fun with the typical man-in-suit Japanese monster film. Whether it is Nitta having a full-on Rocky training montage or the constant fetishizing of his muscles, Kaijyu Mono is not a film that is meant to be taken all that seriously. So, just sit back, relax, and enjoy the show.