People don't like it because it's clearly a rip-off of the more superior Children of the Damned without the alien angle. Plus it's also a left-wing diatribe against the "establishment". It's also far more boring than the better film it stole the plot from.

While the movie does have its problems - the Black Leather song is really lame and annoying, some of the acting barely passable (in Shirley Anne Field's case, frequently well below that) and the dialogue often stilted, but otherwise it's one truly strange picture with a lot of character and sociopolitically relevant things to say. The tragic climax it builds up to, is devastatingly effective. No masterpiece, but certainly an inspired, worthwhile curiosity.
"facts are stupid things" Ronald Reagan

I'm 27, so I'm not sure if I'm still considered too young to appreciate this, but I just got done watching it. This film took me completely by surprise. I thought it would be a straight forward science fiction narrative, so the first half dealing with the beach side resort and the youth gang left me confused, so much so that I thought Netflix had delivered me the wrong film.
The switching of genres, almost like Alfred Hitchcock's "Psycho", can catch the viewer off guard. The film's tone is depressing and dark, the crisp black and white cinematography adding to feeling of disillusionment. I wouldn't say this is a great film, but would make it high up on a list of bizarre cinematic oddities. I'm sure a repeat viewing would improve my feeling on it, but for now all I can say is that it was one of the more unique cinematic viewings I've had in awhile. Superior production quality also make this stand above other genre films of that period.
I'm a stranger here myself
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very good movie. I don't get the hate either. I had never even heard of it till today.
I at first thought. I don't know if I like this. but I did!
it drew me in and I am glad I watched it. though most 'younger' people wouldn't be into this. I know many who would appreciate it. sadly most younger people today only know and like what they see NOW. which is really too bad. it seriously limits them in terms of the subject of the era. being stuck in cell phones, Facebook and Instagram is not really very interesting. I am so glad for TCM!

just watched for the first time on turner classic movie channelvery creepy and the endingnever saw it before, thought I'd seen all the fifties sci fi x the unknowbn is starting now off to watch it

I'm glad that I have got to see this film at last. It's a good piece of cross-genre IMO. I wonder if motorbike gangs were always that menacing in the 1960s. It seems very evocative of what the early 1960s was like. But not quite that menacing all of the time. But the threat of the bomb must have been an influence on this film I think.

right! I don't get the hate I just saw this for the first time last night, and was convinced that I was just watching a teen gang film for the first half! which was, of course, great because the leader was Reed! Then when the film switched gears wow!
Plus, that bizarre/bad/catchy song about black leather made me wonder if I was watching a psychotic remake of West Side Story!
Truly a great film!!