Being a superhero is a dangerous business in Matthew Vaughn’s brutal coming of age tale, based on the comic written by Mark Millar and John S Romita Jr.

Adapted for the screen by Vaughn and Jane Goldman, Kick-Ass is a thrilling, hilarious and at times heartbreaking portrait of teen angst that will undoubtedly raise eyebrows for its heady combination of foul-mouthed, sword-wielding children and graphic violence.

Yet, as recent headlines have brought home with chilling clarity, too many of our youngsters roam the streets with concealed weapons. Childhood innocence died a long time ago.

Kick-Ass taps into modern day lawlessness and senseless brutality by pitting one regular teenager, without a single super power to his cumbersome name, against real life bad guys capable of killing him with a single blow to the head.

“With no power, comes no responsibility,” he rues, lamenting our unwillingness to rush to another person’s aid.

Turning a blind eye to crime is so much easier than taking a stand.

Geeky teenager Dave Lizewski (Johnson) lives with his father (Brown) in New York, where he attends high school and admires unattainable classmate Katie Deauxma (Fonseca) from afar.

“My only super power was being invisible to girls,” notes Dave in voiceover.

During a conversation with comic-book obsessed pals Marty (Duke) and Todd (Peters), Dave wonders aloud if a normal guy could transform himself into a bona fide superhero.

Consequently, the teenager buys a wetsuit off the internet and becomes the heroic Kick-Ass.

Unfortunately, his first forays into crime-fighting end with serious blood loss and a trip to the hospital.

Then the mysterious Big Daddy (Cage) and Hit Girl (Moretz) – aka unfairly disgraced cop Damon Macready and his daughter Mindy – answer the call to arms, thwarting the ambitions of kingpin Frank D’Amico (Strong).

When D’Amico decides to fight back with the help of his son Chris (Mintz-Plasse), Dave is suddenly at the centre of a real life battle between good and evil.

Kick-Ass is an incendiary, fast-paced jaunt though the Big Apple in the company of two motherless youngsters, who discover their strength behind the masks of their alter egos.

Johnson sports an inflexion-perfect American accent as the eponymous do-gooder and Cage delivers his first decent performance for years but it’s pint-sized Moretz who scene-steals from her first blood-spattered skirmish.

Action sequences are directed at a breathless pace by Vaughn – notably a night vision shootout and the storming of D-Amico’s rooftop headquarters – but the visceral thrills never come at the expense of our emotional connection to the characters. They kick ass and we silently cheer them, with clenched fists, from the aisles.