Offensive tells the story of two passive well-mannered retirees from the United States who emigrate to the French countryside and become vicious guilt-free (and expert) serial killers of a gang of anti-social murderous teenagers and co-conspiring cops.
Does that sound a bit far fetched, even for a horror film? Wait until you see some of the finer plot points.
I'll admit, the film does an excellent job of making us dislike the gang of youths and want the adults being terrorised to unleash a bit karma upon them. It even gives us a little bit of satisfaction when the revenge does finally start, so it's not a bad revenge horror/thriller in that sense; and while it's gory it's not over the top in the way that we've seen in many "torture porn" films over the years.
The problem is, it's all a bit too ridiculous even if our belief is suspended to the maximum amount. There are just too many absurd events and explanations within a short space of time, intersected with some extreme murders, for it to eventually become a bit of a chore and thereby preventing it from being as good as the likes of Ils (aka Them).
Perhaps it suffers from the fact that, unlike most horror films, this story has a greater sense of reality since most people have been in a situation where they've felt or been intimidated and harrassed by a group of people, such as those seen in the film, making it more difficult to forgive the unrealistic elements like we can with films containing immortal masked killers.
If you like revenge films then you'll probably enjoy this to some degree, but you may find it difficult to love due to how farcical some of it is.