An actor known for quirky character roles in the likes of Zodiac and Less Than Zero, as well as for his troubled personal life, Robert Downey Jr. might not be most people's first choice to play a super hero. Downey was the best thing that ever happened to TV show Ally McBeal when he joined the cast in 2000, winning a Golden Globe for his role the same year. But in recent years he has managed to get his life back on track, citing among other things wing chun kung fu as a major key to his rehabilitation. With this in mind, his role in Iron Man, of wealthy industrialist Tony Stark – philanderer, womaniser, alcoholic – might not seem such a stretch after all.

The Marvel comics have constantly updated the Iron Man story, dependent as it is on both technology and current affairs, and in this incarnation, the key events take place in Afghanistan, rather than Vietnam as was originally the case back in the 1960s. Tony Stark, riddled with personal demons, is happy to make his millions designing cutting edge military hardware for the U.S. government. However, whilst out in Afghanistan at a sales presentation for his latest super missile, Stark's army convoy is ambushed and he is taken hostage, forced to build weapons for the enemy. Locked away in a cave full of scrap metal and spare parts, Stark – in true A-Team style - constructs a mechanised battle suit in which he is able to blast his way to freedom.

Upon his return to civilisation, Stark is a changed man. A piece of shrapnel lodged precariously close to his heart forces him to construct a protruding neon pacemaker to keep his heart beating. This brush with death, coupled with the horror of seeing his own weapons of mass destruction in the hands of the enemy, is enough to influence Stark to use his talents, and his company, for good from now on. Stark severs his company's military ties and sets to work rebuilding his Iron Man suit for personal use. This comes as distressing news to Obadiah Stane (Jeff Bridges), Stark's business partner, and co-chairman of Stark Industries. Stane has no qualms about selling weapons to the highest bidder, regardless of their political agenda, which instantly puts him at odds with Stark. And it is soon revealed that Stane has been planning his own hostile takeover of the company for quite some time already. Luckily, Stark has best buddy Colonel Jim Rhodes (Terrence Howard) and doting, disapproving PA Virginia "Pepper" Potts (Gwyneth Paltrow) on hand to help him out when necessary.

Iron Man marks Marvel Studios first solo-produced movie, after years of licensing their much-beloved characters - Spider-man, The Incredible Hulk and the Fantastic Four among others - out to other studios, and is a worthy first outing for the character, as well as for the studio.. Director John Favreau (who until now has only directed family-friendly affairs such as Elf and Zathura) confidently plays Iron Man largely for laughs. This is not to say that it pokes fun at its subject manner – on the contrary, the film itself is played dead straight, but at its core is a character so relentlessly sarcastic and jaded, that almost his every line is laced with dry, sardonic wit. And it is largely thanks to Downey's charismatic performance that the film works as well as it does. In fact, one could argue that the action sequences are forced to ramp up the excitement and spectacle to compensate for the fact that Downey is hidden within
his armour.

That said, the film doesn't quite manage to keep up with the fantastic opening third, which is tautly written and executed with confidence and gleeful enthusiasm, but by the final act, the characters have engaged their audience and you are happy to be swept along for the ride without much persuasion. Whether it be Iron Man's revenge mission in Afghanistan, or his final smackdown with Stane, who by this stage has fashioned his own battle suit from Stark's original design, the action sequences more than deliver in terms of adrenaline-fuelled action.

Marvel have already stated that one of their goals is to keep a continuity running through their movies from now on, with recurring characters, played by the same actors, cropping up in different movies. So look out for a brief Downey cameo, as Stark, in next month's The Incredible Hulk, as well as many more crossovers in years to come. What Downey, Favreau et al have proved, more than anything else, is that they are more than capable of holding their own with the summer big boys. Iron Man is big and loud when it needs to be, as well as witty and satirical when it could have been simply bland. As the first tent-pole release of the summer, Iron Man has set the standard for the rest of the pack to follow, and with the likes of Batman, Indiana Jones and The Incredible Hulk all returning to the big screen in the coming weeks, it is shaping up to be one hell of a Hollywood blockbuster summer.

James Marsh