Sometimes in a trilogy the sequel is less popular than the first and third. Take the Gamera Heisei trilogy for example. When you hear about it, people usually talk about the first one and the third one, Advent gets left out. Why? Well, Gyaos was always the fan favorite, along with Iris. Somehow Legion never became a favorite, it's quite disappointing. Advent takes some new and old concepts to make a fantastic follow up to Guardian of the Universe. It's similar, yet completely different. Advent of Legion takes some of the faults from the previous film and improves upon them. No more bad CGI or fake looking props, we have a kaiju film with near perfect special effects, and a good story to back it up.
The story begins when a meteor shower comes to Japan. As expected, these aren't ordinary meteors. Soon in the sewer people are getting killed by one-eyed insectoid creatures. The military is sent in. What they find is something growing, and a bunch of these insectoid creatures dubbed 'Symbiotic Legion.' The soldiers are quickly taken out, and soon the building above is covered in a giant pod. Soon after Gamera rises out of the water to destroy the pod. After he destroys it with a fireball, the 'Big One' rises out of the ground. This adult Legion may prove too powerful for Gamera.....
The last time a kaiju film used insectoids was in the original Rodan film I believe. This time these insects are from space. Alien insects, that's a good combination. (You're probably thinking of Starship Troopers right now.) This might be a stretch, but I think Godzilla vs. Megaguirus borrowed some concepts from this film, such as all the smaller insectoids going all over the title monster. Anyways, this film is different than the previous one. Gamera has been established, and appears when there's trouble. The first fifteen minutes or so are painfully slow, but gets better later. This film has some of the best fights in any kaiju movie, a good mix of slugging around and projectiles. The final battle feels climatic, not slow, and just very well done. The characters once again do a good job carrying the film when there's no monster action happening, though I gotta say that I preferred the characters from the previous one.
Mayumi is replaced by Midori as the central human main character. While she can't compare to Mayumi, she's still pretty well-written, something the majority of the Heisei Godzilla films can't really say. Asagi returns, but got a smaller role than I remembered. She almost had no significance other than to reassure people that "Gamera is coming" and "Gamera is alright." The whole link thing still doesn't make much sense. Other characters are well enough, though Osako returns for another awful role. Truly the worst written character in the whole thing. I have to question some of the writing. In the third act, a commander says "Why should we help out a monster?" while Gamera is getting beat up by Legion. Besides that, the writing is solid.
Gamera is looking once again fantastic. It's just an amazing suit, truly one of the best from any kaiju film. It's just fluid, menacing, yet not too menacing, it still gives off his heroic demeanor. Legion is the new opponent here. Her design is one of the most unique I've ever seen, truly a highlight of the film. She has some really interesting abilities, and a cool, yet creepy roar. Something this massive could have been not displayed well, but the film does it, and does it well. The CGI sequences with it look fantastic, especially when she rises out of the ground. Its just a treat to watch this massive creature on the screen. The Symbiotic Legion soldiers are also very good, some of the best props I've ever seen in a kaiju film. Legion is probably one of the most underrated kaiju of all time, which is disappointing since she is the toughest opponent Gamera has ever faced.
The soundtrack isn't much different from the previous one in terms of quality. That' means it's a solid soundtrack, but could have been better. Granted, it has some thematic themes, but can't compare to any of the Heisei Godzilla films' themes. Even though this is a giant monster movie, there are some intense scenes with the humans This is probably one of the grittiest Japanese kaiju films ever. To this day I find the train scene near the beginning brutal. Whoever said Japanese monster movies can't be this hardcore hasn't seen Advent of Legion. Both Gamera and Legion have personality, it's good stuff.
Overall, Gamera: Advent of Legion does exactly what it set out to do: be a worthy successor to Guardian of the Universe. It took some of that film's faults, (some of the bad special effects) and improved upon them. It features one of the most interesting kaiju of all time in the form of Legion, fantastic monster fights, and a good story. Truly, this film is one of the best in the genre.