Given the talent involved, Paul should really be better, smarter and funnier than it is. A bit of disappointment coming from actors/writers Nick Frost and Simon Pegg, whose Shaun of the Dead and Hot Fuzz were terrific genre-savvy romps, this ode to sci-fi geekery is almost disturbingly flat and uninspired for the most of the running time. The premise of a pair of English sci-fi fanboys going on a road trip across America visiting UFO sites has great potential for some wild comedy and ideas, but the film traffics in tired chase-flick conventions, sophomoric gay humour, standard swipes at Christian fundamentalist nutters and American rednecks and ends on a note of such lame, unoriginal in-jokiness the only reaction I could muster was instant revulsion. The best thing that can be said is that it does have a genial tone, which makes the lackluster moments somewhat watchable if not exactly satisfying. Seth Rogen’s titular CGI alien is exactly how you’d imagine Seth Rogen voicing a little green man.