From the very opening frames of Iron Man 3, anyone familiar with your work will recognize it as a Shane Black film: the staccato stream-of-consciousness voice-over, the trilling notes of a goofy pop song played for laughs. This sort of quick recognition is pretty impressive, considering you've only directed one other movie (the self-referential neo-noir flick Kiss Kiss Bang Bang). Impressive, too, that you managed to retain a bit of your idiosyncratic style in what is perhaps the most constraining situation imaginable: a studio-financed franchise worth mega-millions.
What's most astounding, however, is how you managed to turn the third chapter in one of the most popular modern comic book adaptations into another loving ode to film noir.
Kiss Kiss was the beginning of Robert Downey Jr.'s Hollywood redemption tour (his character Harry Lockhart was Tony Stark with training wheels; all the charm and ego, none of the money), and it's a wonderful bit of kismet that you guys are reunited, here, with the vast resources of Marvel Studios and Paramount Pictures behind you.
So, how do you indulge? You keep Tony Stark outside the Iron Man armor for most of the movie, treating him instead like an good noir foil: a man betrayed by his own hubris, whose greed and misanthropy come back to bite him in the ass. After a series of attacks wrought by Ben Kingsley's implacable super-terrorist The Mandarin, Stark follows clues like a good private dick, escaping from trouble not through the use of brute force, but rather by a bullet-headed persistence and a good deal of blind luck.
The noir hero is rarely invincible or infallible; the private eyes and aging boxers and struggling conmen who populate the genre are hardly ever in control, and neither, in this film, is Tony Stark. He's struggling with post-traumatic stress after the interdimensional shenanigans in the last act of The Avengers, and suffers constant anxiety attacks that threaten his most precious resource: his ego.
It's difficult in a movie beholden to the rhythms of a modern Hollwyood blockbuster to earn a genuine surprise; we're all so familiar with the conventions that even when they're broken it feels expected. However, the turn that the plot takes with The Mandarin feels genuinely refreshing (and finding something refreshing within genre orthodoxy is kind of your specialty: more proof that this is, through and through, a Shane Black joint).
The secret of the Iron Man movies has been that they've managed to avoid the crippling self-seriousness that drags so many current comic book adaptations to the bottom of the ol' Nietzschian muddy waters (I'm looking at you, Amazing Spider-Man). And that's why you were such an obvious choice to make this movie. You may not have invented the action-comedy, but you were certainly a founding father of its tropes and traditions. Lethal Weapon may have aged poorly, but that's only because it's the foundational text from which the prevailing common language has sprung.
But here we are talking semantics and thematics. A Shane Black movie, above all else, is entertainment. And Iron Man 3 is nothing if not entertaining (says the guy who has trouble remaining objective). And not simply entertaining in the traditional manner of CGI-fueled summer popcorn fare. The way you confound expectations by setting up heroic moments for Stark and then letting them sputter to a stop feels subversive, somehow, and even though we get the whiz-bang finale where the hero and villain (Guy Pearce going full Alan Rickman) find themselves face-to-face and fist-to-fist atop a tower, the self-awareness that runs beneath it ("Here we are, on the roof," Pearce says) makes it feel like it's all on purpose.
And though film noir is defined by a moral ambiguity and bleakness which Iron Man 3 certainly lacks, it is always driven forward, as the gears turn and the latches click into place, by a sense of inevitability, a feeling, indeed, that it's all happening on purpose. And that, I think, is where much of the joy of a Shane Black movie comes from.