The Door Into Summer is a time travel adventure combining romance and humour

Kento Yamazaki (left) as Soichiro Takakura and Naohito Fujiki as a humanoid robot in The Door Into Summer. (Screenshot: Netflix)
Kento Yamazaki (left) as Soichiro Takakura and Naohito Fujiki as a humanoid robot in The Door Into Summer. (Screenshot from Netflix)

After starring in the Japanese thriller Alice In Borderland, Kento Yamazaki returns with his latest film The Door Into Summer, which is now streaming on Netflix. The film is based on the novel of the same title by Robert A. Heinlein.

Yamazaki portrays a pioneering roboticist Soichiro Takakura, who seems to bring about bad luck to the people around him. Having lost his parents at a young age, Soichiro is taken in by his father’s friend Matsushita. His life is peaceful until Matsushita and his wife pass away as well, leaving Soichiro behind with their daughter Riko (Kaya Kiyohara).

As if their deaths are not depressing enough, Soichiro also loses control of the company that he and Matsushita had poured all their time and effort into. After an incident puts him in cryo sleep, he realises he is now in the year 2025. Now, he has to find a way back to 1995 and reunite with his adopted sister.

Here’s how The Door Into Summer is a film that covers not just sci-fi, but also romance and humour:

1. It carefully plays on the time travel theme.

The problem with time travel stories is that it's challenging to avoid time paradoxes. Often, it's assumed that time travels in a linear fashion, but going back in time to fix the past will create an endless loop in the timeline. Many dramas and films fall into this trap, which inevitably results in an incoherent plot.

However, this is not the case for The Door Into Summer. They introduced the concept of parallel worlds to the story, and made it clear that Soichiro is in a re-written future. This explanation rectifies the issue of the time paradox, although there is still a nagging feeling that something just doesn’t add up.

Nonetheless, if you put that behind you, The Door Into Summer is rather fascinating to watch. Besides, the cryo sleep machine is also another kind of time travel, which will remind you of Marvel’s Captain America.

2. There is an unspoken and somewhat forbidden love between Soichiro and Riko.

Soichiro and Riko are siblings with no blood relation, which makes their relationship complex. While it is obvious that Riko harbours feelings for Soichiro — hovering around him and taking care of things for him — the feelings Soichiro has for Riko are more ambiguous, alternating between romantic and familial love. The ending of The Door Into Summer comes as a pleasant surprise, providing a heartwarming conclusion to the sub-plot on the relationship between Soichiro and Riko.

3. Naohito Fujiki plays a comical humanoid robot.

The Door Into Summer is set in a world with humanoid robots, and Naohito Fujiki plays one of these robots named Pete 13. As it turns out, Pete 13 is a defective robot with an "'explore' function overload", said to be “the equivalent to curiosity in humans.” As he learns about the world, he begins to play an assistive role in Soichiro’s journey, and simultaneously becomes the comic relief with his strange antics. Fujiki also did well portraying the stiffness and emotionless aspects of robots.

4. The colour grading enhances the film.

As The Door Into Summer is set in both 1995 and 2025, it makes use of colour grading to differentiate between the two time periods. In the 1995 scenes, an orange-yellow tone is applied to generate a feeling of nostalgia and to signify the past. On the other hand, a blue tone is used for the 2025 scenes to give a futuristic feeling. The way the colours are used adds an artistic layer, which enhances the experience of the film.

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