One thing the script does do really well is deliver some jolting surprises, especially in the first half hour or so. There are a couple of totally random, out-of-nowhere events that I didn't see coming, which help propel Tom Cruise into the plot proper. Without giving too much away, Ethan Hunt gets sprung from a Russian prison (see clip at left) and is sent on a mission to discover the identity of a Russian traitor whose sexy henchwoman has stolen some nuclear launch codes. It all goes about as well as the mission at the start of a Mission Impossible movie ought to, and Hunt and his team get blamed for an act of terrorism in Moscow. Soon, they're all disavowed by the U.S. government, and they have to stop the real terrorists without any government support.

There is a lot of winking throughout all this — despite the team being disavowed by the government, the movie still manages to have someone say "your mission, should you choose to accept it" about a dozen times.

The script is written by Josh Appelbaum and Andre Nemec, two former Alias writers who also created the U.S. version of Life on Mars — and it's very much like an Alias episode, even more than the previous J.J. Abrams-directed installment was.

So yeah, you can't take the story in this film all that seriously — but the good news is, you don't have to. This is much more comedic than the last two more tragic/dramatic Mission Impossible films were. Everybody involved seems to have made a conscious decision to amp up the hijinks and jokes, and dial back the angst and hand-wringing. The first big action scene is a prison break to the tune of "Kick in the Head" by Dean Martin, and the first big mission, after that, involves Simon Pegg in disguise as a Russian army officer, which you can just imagine how that goes.

Honestly, I was giggling like a maniac during large parts of this film — both at the intentional humor, and at how ridiculous a lot of the plot wrangling is. (At various points during the long Dubai sequence, Pegg or Renner points out a much simpler, more sensible option than the ridiculously elaborate plan that Cruise has come up with — only to be shot down because spy jargon spy jargon spy jargon.)

Also ridiculous and awesome: all of the gadgets in the film. Including contact lenses that can scan a document with two eye-blinks, causing an exact photocopy to print out inside a nearby briefcase. (The briefcase can also print out an exact copy, with some of the numbers in the document scrambled, just as instantaneously.) There are also magic holographic screens, Minority Report-style car windshield displays, and tons of other crazy science fictional toys.

And definitely, adding Renner to the mix and amping up Pegg's role in the film turn out to be two very good ideas, both because they're funny and because an ensemble cast takes some of the emphasis off Cruise. Pegg has some funny bits with Cruise early on, but once Pegg and Renner start playing off each other, it's instantly better. Just check out these two clips from a bit where Renner is going to jump into a computer room and Pegg is going to catch him:

Cute, right?

Although some humor in the film doesn't work quite as well, like the whole bit where Paula Patton has to seduce a rich Indian businessman (Anil Kapoor) to get some satellite codes from him:

Patton is the fourth member of the ensemble, and she's probably the weakest of the bunch, although she does get a few good moments here and there.

Then there's the third reason why this film actually works quite well — Brad Bird directs this movie as if he may never have another chance to direct an action movie again. And he's clearly madly in love with IMAX cameras and their ability to turn a huge action sequence into a ginormous action sequence. The main action in this film takes place in a few picturesque locations — Russia, Dubai and Mumbai — and Bird takes every bit of the setting and makes it as huge and as intricate as he can. Even the setting of the final fight scene, a vertical Mumbai parking garage, turns into a deadly geometric puzzle, akin to the whole "doors" sequence at the end of Monsters, Inc.

I've seen a lot of people praising the action in this movie because you can tell what's going on, and who's doing what, and things seem to happen in sequence. It's really sad that we've reached the point now where we have to praise action movies for having coherent action. But it's true that I was never confused — or bored — by the action in MI4.

With one exception — the "sandstorm chase" scene, which you can see a bit of at left, is one of the most dazzlingly ambitious and intentionally confusing chase scenes ever. And even then, Bird keeps it tight and makes it easy to figure out what's going on. When you see it on the huge IMAX screen, it's just pretty astounding.

Which brings me to a recommendation: See Mission Impossible 4 in IMAX, or wait for the DVD. I really think those are the two choices. It's not really a brilliant enough movie to see on the big screen, unless you can really get swept away by the huge visuals on a massive IMAX screen. I have a feeling it would be a lot less fun in a regular theater, with regular theatrical resolution, and it might start to feel more like a generic-but-funny spy movie.

There's a reason why this film is getting its first release in IMAX only, with non-IMAX screens being added next week — the buzz would probably be a lot less buzzy otherwise.

If you can see it in IMAX, though, I'd definitely flock to see Mission Impossible: Ghost Protocol this weekend. It's a seriously fun movie, in which Simon Pegg and Jeremy Renner get to have a buddy comedy on the sidelines and Tom Cruise isn't nearly as annoying as you think he might be. Mostly, it's a triumph of Brad Bird's visual sense and action sensibility over all the tired spy-movie formulae.