In a film that define follower of the social message of Romero is little, there is a lot of will, little money but, unfortunately, no one really believes in it. There is the versatile Catalan director Jorge Grau that leaves to a cast with Ray Lovelock, Arthur Kennedy and Cristina Galbò the more attractive names.
The premises, it can be said, that they are not the best but with a big surprise comes an interesting film, well directed and well develop with a very original theme for the times: the progress and the desire of the human to subvert the natural order. An argument developed in parallel with the classic generational clash.

Themes well-developed with no useful rhetoric at the service of a horror that optimally exploits the British landscapes. Grau is skilled in underline darkness and negativity of the places, in which the main players are moving well, creating interesting characters. A surprise ending then closes what is a fine example of genre films, ignored in a total way in Italy and appreciated abroad, before the more classic revaluation.
Shot at Cinecittà in Madrid and in England, the film sometimes slips on narrative shortcuts that make it easier the course of events. The zombies aren’t a masterpiece but they are functional to the story, thanks to the skill of Giannetto De Rossi.

A streaker who ran naked through the traffic opens the film (a scene not original but purchased for the occasion) making us already understand the clash between young and conservative. Then it's up to the beauty of the genre cinema, Ray Lovelock. Bearded and wing long hairs Lovelock is George, a boy who runs on his motorcycle for met a few friends. At a gas station Edna (Cristina Galbò) collides with his car damaging the motorcycle. The two leave together in the car, making a small detour at the house of the sister of Edna.

The place is lost in the rainy English countryside and strange creatures wander around the place killing the husband of Edna. The police led by a hyper conservative commissioner, played by Arthur Kennedy, investigate the incident accusing the three young. They try in every way to route the police towards these murderers’ monsters. Zombie generated by ultrasound of an agricultural machine that eliminates the parasites.
The stupidity of those who want to preserve the status quo and who is ready to sacrifice everything in the name of progress does increase the problem, which culminates in the small hospital of the town with a scene reminiscent the work of Romero.
A nice horror chapter massacred by an endless series of versions of titles that often exclude the most splatter scenes (like cannibalism at the cemetery or the nurse slaughter) but the research of uncut version is then rewarded by the view of this little gem.