It seems not everyone "gets" Slither. It's accused of lacking scares and humour, but the film isn't really about either of those. The horror is intentionally mild, stupid and exaggerated as the film is an homage to the classic movies of the 1950s. Y'know, the ones with the giant creatures wrecking cities and aliens zapping sheep with rayguns? Yeah those. They were terrifying back in the day yet somehow still enjoyable in our modern age, and that's what Slither attempts to reproduce with it's corny, light-hearted tale of alien infestation.
The humour isn't derived from well-written and superbly delivered witticisms or painfully true observational stabs at modern-day society, it's not even derived from the stupid young American teenager who thinks that beer and breasts are the best punchline to any situation. It comes from the sense of nostalgia you get, when by watching Slither you somehow feel as though you're watching a much older film and think "People used to be scared by this?!". The film mocks the intelligence of the viewer by intentionally giving them something they might have been terrified or amazed by had it been released 60 years ago. Less than that even, there are subtle references to classic 80s invasion movies too, such as the now-laughable-but-once... laughable Critters series of films.
All of this is tied together nicely with the cleverly done (or edited) camera work and production on the film which gives it that 80s VHS film grain effect, I was almost convinced I'd just pulled this masterpiece out from the back of the cupboard, it managed to bring back good memories instantly despite the fact I'd never seen it before in my life, and that alone is worth an extra star.
This film isn't specifically aimed at the modern horror audience (and let's face it, they're getting tamer anyway - replacing fear and tension with cheap shocks? Fascinating.) although anyone with a decent knowledge of horror film history should find something to enjoy here. We need more of this, horror movies are at their best when they're injected with an element of fun (Evil Dead 2 anyone?) and the last couple of decades have been severely lacking in the fun department. Slither is truly a bright apple in a basket of rotten fruit.