Full disclosure: one of the associate producers of this film is a friend of mine from college. Once, he directed a movie that I production designed. Now he's a Hollywood executive and I blog. I'll try to keep my spittle-flecked jealousy from spilling into the review.

Iron Man is a film straddling a knife's edge between being extraordinarily good and being effective middleweight entertainment, and the difference between those two points is the difference between two men: Robert Downey, Jr. and Jon Favreau. Both rather odd choices to lead a comic book movie and summer tent pole, and only one of them earns the title of an inspired choice.

In the first film self-financed by Marvel Studios, Downey plays Tony Stark, the Howard Hughes-inspired crazy industrialist who we first saw in the spring of 1963 building himself a super-powered suit of armor to escape from the Vietnamese prison where he was held captive. That's been tweaked a little bit, of course: now it's an Afghanistan warlord who captures the weapons developer Stark, visiting the US military on a sales trip.

In all his incarnations in all media, however, one thing remains constant: Tony Stark is a playboy who likes expensive toys and gorgeous women, and has something of a sense of entitled superiority. If this sounds like the kind of role that professional sarcastic asshole Downey is very good at playing, it should: Downey is very good in the role. "Very good" is underselling it by a considerable margin, actually. In Downey's hands, Tony Stark instantly becomes one of the great characters in the whole of the superhero movie, creating a figure that can stand alongside Christopher Reeve's Clark Kent and Christian Bale's Bruce Wayne, and pretty much nobody else. Downey-as-Stark is the beating heart that makes the whole movie tick, mixing humor and a slightly desperate edge and scuzzy charm all up in a cocktail of character psychology that is rarely seen in a comic book movie and never as much fun as it is here. It's thanks to Downey that I realised that this film of Iron Man isn't about Iron Man at all; it's about the man who chooses to pretend to be Iron Man, and why he does it (in this as in many ways, the film is quite close to being a retread of Batman Begins, except without brutal nihilism).

And as good as Robert Downey, Jr. is for Iron Man, so is Iron Man good for Robert Downey, Jr; I'm honestly not sure that I've ever seen the actor in a role with quite as much range as Tony Stark (the comic book movie ain't what it used to be, kids). He's a raconteur, a guilt-ridden bomb-maker, an avenging angel, the smartest guy in the room, and it's rare that he only has to be one of those things at a time. Downey's versatility in gliding through Stark's emotions is something to behold, and prove (if we needed it) that he's one of the most capable actors in the movies today.

Ah, but I did promise that the film was on a knife's edge, didn't I? Iron Man was directed by Jon Favreau, a man whose name is likelier to call to mind Swingers, which he didn't direct, than any of the handful of films which he did. Since that handful includes Made, Elf and Zathura, it's an open question whether that association helps or harms Favreau's reputation. But this much is clear: he's not necessarily the strongest director to ever helm a blockbuster. Without question, Iron Man is his greatest film, and much of what makes it work is entirely the director's fault: it was his innovation to encourage the actors to ad-lib (like "a Robert Altman-directed Superman" says the director), he chose to represent the Iron Man outfit using practical effects whenever it was remotely possible to do so, and I assume he has something to do with the film's effortless pace, in which a 126-minute film seems far, far too short. No mistake, Iron Man is a hell of a lot of fun, and a great start to the summer season, and the bar has definitely been raised for the next three months. You'd have to hold a personal grudge against the idea of comic books not to find it a delicious entertainment.

Thing is, we're in a very rare moment where superhero movies get to be more than delicious entertainments; at their best, they can be legitimate great cinema by any yardstick, not just the stunted knobby one we use to discuss popcorn movies. And that takes a stronger authorial voice than Favreau is capable of offering. Think about the great movies in this genre in the last decade: Spider-Man and Spider-Man 2, X2, Batman Begins. Each one of those films had a clear personality, and each of those films was made by a filmmaker with a strong voice. Admittedly, two of those films aren't much "fun" in any useful sense, but the Raimi films in particular prove that you can have a roller-coaster movie that also has a lot art backing it up.

I'm not saying that Iron Man doesn't have strong themes; I'm not saying that it's bad in any possible definition of that word. I'm not even saying a strong personality is the only thing that makes a comic book movie worthwhile; Hulk and Superman Returns had personality. I'm saying that it feels kind of disposable, without the sort of iconography that makes you think about it for days and weeks, trying to figure out how it works. It's a lot of fun while you're watching it, but it doesn't wedge itself in your head. It doesn't force us to reconsider the possibilities of what a comic book movie can be. It's a solid entertainment, and while it's easy to wish it were more than that, it's worth pointing out how much less it could have been. Put it another way: if this turns out to be below the top tier for the year's blockbusters, we're in for a hell of a summer.

Other MCU reviews (Phase 1)
Iron Man (Favreau, 2008)
The Incredible Hulk (Leterrier, 2008)
Iron Man 2 (Favreau, 2010)
Thor (Branagh, 2011)
Captain America: The First Avenger (Johnston, 2011)
The Avengers (Whedon, 2012)