2. 21 Jump Street
In this surprisingly smart and self-referential comedy, Channing Tatum and Jonah Hill play Jenko and Schmidt, two undercover cops sent back to high school in order to track down the supplier of a synthetic drug known as HFS (or, to give its full name, Holy F***ing S**t. You'll recognise it by the little picture of a turd with a halo). Finding the source is easy enough but proving that they're not cops requires the ultimate challenge: to try HFS for themselves. Reluctantly, they accept- only to stumble into the path of their PE teacher, Mr Walters (the ever-brilliant Rob Riggle), on their way to class. And it's at this precise moment that the drug starts to kick in... The film is worth watching for the following exchange alone. It is immediately clear that something isn't quite right; what with Walters' face morphing into an ice cream cone, prompting Jenko and Schmidt to flop out their tongues. Their teacher is rather unnerved by this, but by now his eyebrows have crawled along his face like caterpillars and formed a moustache. Again, the boys are struggling to contain themselves. In fact, the more Walters' suspicion grows, the harder it is for them to keep calm; until finally he can wait no more. ''Are you guys on drugs?'' he asks. And then everything explodes.