It's the first instalment in a two-part live-action movie adaptation of Parasyte, the esteemed 1988-1995 manga that can be thought of as "what if The Thing was just one of an entire species and they all landed in Japan?" The 2014 anime adaptation I loved, but this film is pretty good too.

It doesn't feel crunched. Obviously it is, compared with a ten-volume manga and a 24-episode anime, but you wouldn't guess if you didn't know. It feels as it belongs at this length. You don't sense compression.

The protagonist is Shinichi (Shouta Sometani, husband of Rinko Kikuchi) and his right hand, Migi. Shinichi is a seventeen-year-old schoolboy. One night, an earwig tries to crawl up his nose before burrowing into his arm. (Note: it wasn't an earwig.) He stops it from getting any further with an improvised tourniquet, which is good since it means that Migi only eats his arm, not his brain. His arm looks normal, but it's now an independent alien being. From then on, his right hand is liable to act on its own and start doing things like:

(a) grope a girl's boob in the middle of the street

(b) stretch out like silly putty to grab something he dropped

(c) grow an eye

(d) start talking to him

(e) react badly to being threatened with a knife. It's a lot like Terminator 2. Migi can turn its body into blades and cut people up.

However the earwigs that reached their hosts' brains have taken control of the entire body, which is scarier than a seventeen-year-old boy who keeps arguing with his hand. We don't know how many parasites there are, but it's probably "a lot". Their favourite food is humans and they'll generally start by biting your head off. The first victim we see is the parasite's host's wife. Shortly afterwards, we hear the children come in from school and the parasite goes to meet them.

I have a feeling that there's less black comedy than I remember in the anime, but it's still fun in a gruesome, horrific way. We get to see Shinichi and Migi infecting each other. Shinichi becomes ever more emotionless and Migi-like, especially after a certain incident, while the amoral Migi grows the ability to sleep and get excited. (That sleeping is inconvenient and dangerous, mind you.)

The human characters don't get a huge amount of screen time, except of course for Shinichi. There's still Satomi (Ai Hashimoto) and I liked her, but the film's spending more time exploring the parasites. They eat people, yes, but what if they also started getting clever? What if one of them was your teacher, capable of impersonating a normal member of society and educating young people? They could be policemen. They could do what Tamiya does, which is going to get even more eyebrow-raising in Part 2. They might even start running political campaigns and winning elections. (Would you vote for them? Would they necessarily be worse than some actual world leaders?)

Sometani's decent in the lead role. There's a CGI flame explosion, but it sort of looks okay and otherwise the production values are solid. There's a lot of CGI, obviously, but all the monster special effects are solid. I also particularly appreciated the parasites looking as they do in the manga. Migi looks like Migi. He's ugly-cute. You've got to love the adorable little horror.

It's a good film, I think. It's SF/horror, obviously, with the narrative more interested in exploring aliens than humans, but the latter aren't being neglected. Sometani, Hashimoto and Kimiko Yo (as Shinichi's mum) are all important, not to mention a cop who'll presumably become more important later on. I'm looking forward to Part 2. Should be good.