Parasyte the Movie: Part 1

Live action feature based on the Japanese manga series by Hitoshi Iwaaki.

When a species of alien invades Earth and takes over humans' bodies by crawling into their ears and inhabiting their brains, headphone-adorned teenager Shinichi Izumi (Shôta Sometani) escapes the same fate, but doesn't get away completely unharmed.

Unable to access his victim's ear, the alien decides instead to set up camp in Shinichi's hand.

Realising that there is no way for the creature to die without also killing Shinichi, the unlikely pair team up to try to stop the rest of the world being taken over by parasites.