The 2002 Japanese science fiction film "Returner" is a hidden gem that has managed to fly under the radar for many years, despite its intriguing premise and impressive action sequences. Directed by Takashi Yamazaki, the movie tells the story of a young woman named Milly who travels back in time from a post-apocalyptic future to prevent an alien invasion that will wipe out humanity. She enlists the help of a local gunman, Miyamoto, who is initially reluctant to get involved but eventually finds himself drawn into the battle to save the world. With its unique blend of science fiction and action elements, "Returner" is a thrilling ride that will keep viewers on the edge of their seats.

One of the standout aspects of "Returner" is its well-crafted storyline, which seamlessly weaves together elements of time travel, alien invasions, and human drama. The film's pacing is well-balanced, with a mix of intense action sequences and quieter moments of character development. The special effects, while not as polished as those in modern sci-fi films, hold up surprisingly well even by today's standards. The movie's themes of time travel and the consequences of altering the past are also thought-provoking and add depth to the narrative. The chemistry between the two leads, played by Anne Suzuki and Takeshi Kaneshiro, is also noteworthy, and their characters' banter and interactions add a welcome layer of humor and humanity to the film.

Despite its many strengths, "Returner" is not without its flaws. Some viewers may find the plot twists and turns to be a bit predictable, and the movie's villain is somewhat one-dimensional. Additionally, the film's ending feels a bit rushed, and some plot threads are left unresolved. However, these minor quibbles do not detract from the overall enjoyment of the film. Overall, "Returner" is a fun and entertaining sci-fi action movie that is sure to appeal to fans of the genre. With its unique premise, engaging characters, and thrilling action sequences, it is a must-see for anyone looking for a hidden gem from the early 2000s. While it may not be a perfect film, "Returner" is a wildly entertaining ride that will keep viewers on the edge of their seats from start to finish.