10. The Exorcist
You knew it had to be on this list.
Where a lot of iconic, classic horror masterpieces are more atmospheric or influential than outright scary (hi there, Stanley Kubrick's The Shining and John Carpenter's Halloween), first time viewers are likely to be blown away by how relentlessly effective William Friedkin's 1973 classic The Exorcist remains decades after its initial release.
Yes, it's hugely famous, widely parodied, and as such feels like it couldn't possibly hit hard any more.
But it's a combination of the film's slow, deliberate pace and the regular sudden jolts of terror that makes it so enduringly anxiety-inducing, as well as some still-taboo shocks and clever filmmaking tricks. The subliminal inserts shots of the demonic Captain Howdy leave the audience constantly on edge, unaware why they're unsettled but nonetheless shook. Meanwhile, whilst onscreen effects and gore may have grown more explicit in the years since its release, few mainstream releases have managed to include imagery as gasp-inducing as the film's infamous crucifix sequence.
Still the greatest to ever do it, this iconic horror manages to be as gripping as ever thanks to sequences that no amount of parody can soften the effectiveness of.