Homaging a style is tricky enough, but to do so while giving a film its own unique edge is damn near impossible. Even great directors can fail here, delivering strong replicas that don't give up anything in their own right. So let's hand it to David Robert Mitchell. It Follows was deeply inspired by the revolutionary genre work of the early eighties - it features a backdrop and visual style just two blocks over from John Carpenter's Halloween and music that feels like it could have sprung from Vangelis' synthesiser - but also a unique, progressive horror film in its own right. The key genius decision, however, doesn't come from style, but from concept. The movie's monster (the titular It, which quite literally follows its victim forever) is set up as a simple STD allegory - haunting is passed on to other people through sex - but as the film progresses it becomes clear "It" is actually a metaphor for something much more universally haunting and imposing - death itself. The ultimate suggestion of acceptance through the power love is a strong one that goes up against any expectations of a more sexually inclined film. In the wake of its immensely positive reception, some have laid into the film for being an overrated - it doesn't follow its own rules fully and isn't as transgressive as those which inspired it - which smack of knee-jerk reactions to overhype; taken on its own terms it's impossible to not conclude It Follows is 2015's best horror film.