V enjoyable superhero flick that does exactly what it says on the tin. Adapted from the comic by Mark Millar and John Romita Jr, it follows the adventured of Dave Lizewski (Aaron Johnson) a high school fanboy who asks a simple question and then follows it to its logical conclusion: why hasn't anyone tried being a superhero?
After a few half-assed encounters with some low-level street thugs (basically involving him having his ass-kicked), his scuba-suited antics get picked up on YouTube and he becomes something of a local hero. This brings him to the attention of a far more organised duo - Hit Girl and Big Daddy (Nicholas Cage on great form) - who show him (and us) what real-life vigilantism would actually look like - basically, some unhinged people running around with a lot of guns and weapons.
The action is fast-paced, the nods to comic books on form without being overbearing (one flashback scene all told with comic panels is brilliant), and the dialogue a deft balance between hilarious and daft. Aaron Johnson (last seen as the young John Lennon in Nowhere Boy) is an engaging lead, Christopher Mintz-Plasse (aka McLovin in Superbad) has a good sense of comic timing, and it's always good to have Nic Cage in a role where you don't hate him for not being as good as he used to be. 12 year old powerhouse Hit Girl is a force of nature too, she gets some of the best lines, and this could easily be a breakout role for Chloë Moretz.
Chuck in the odd disarmingly moving scene, some gore-packed fights and a plot that keeps just the right side of almost-believable, and it's a winner. Totally not suitable for kids though, will be interesting to see how well it does without an underage superhero audience packing it out (although, let's face it, there are probably more than enough grown-up superhero fans around these days...).