The script is intelligent, the direction is smart, the "camera move" is supreme and Simon Pegg's performance is outstanding. It's a black comedy with a rather 80's touch that renders the whole atmosphere so mystical and hysterical. The humor is totally "black" orchestrated with extreme behavioral moods, spastic grimaces, and unbelievable dream sequences that you'd love to watch over and over again. The character Simon Pegg is playing, is a kind of paranoid intelligent looser that is trapped between 2 worlds. The fears and insecurity he has carried over from the past (as a kid) have reached a point where they've become phobias, projecting outwardly in schizophrenic behavior. The character believes or rather is obsessed with the idea that he is going to be murdered. I am not going to say anything more about the plot as it's worth seeing it afresh.
This film captures some amazing ingredients of good black comedy films: mystical atmosphere, sound/music synchronization with sudden camera moves, funny faces (extreme), smart script, dream sequences and spontaneous direction. It's British humor, which I personally love, with a few deeper meanings (behind the whole phobia thing projected from a traumatized subconscious which tries to come to peace with the past).
Having read a few other reviews before watching it, I must say that I find it sad that people expect American style productions and high budgets in order to like a film. How rare good comedies are these days? I loved the film and if you like black comedy and other Simon Pegg's movies I suppose you'll at least like it, since it carries a cinematic seriousness in its humor.