One of the few things Kangaroo Jack does right is digitize the kangaroo. I'm not a big fan of digitization if the real deal is readily available, but in this case, it's just too hard for me to picture a real kangaroo creating the physical expressions the 'roo known as Jackie Legs performs in Kangaroo Jack.
Kangaroo Jack is a Jerry Bruckheimer-produced movie without the requisite explosions. Knowing this, are you interested in it at all? If not, fine. We've apparently both got time to kill, so I guess I'll fill you out on all the other pointless details.
Kangaroo Jack isn't even the star of the movie, despite the pleading of Jack at the end for the director to close out the movie with his image. You would have to do a little bit of stretching to even call him the focal point. Despite the personality he shows in the end outtakes, the character himself is just an ordinary, average, everyday kangaroo. He doesn't say anything, he doesn't rap, he doesn't breakdance. He does give the main character a booting, but that's such a tired gag nowadays that it's hardly even worth mentioning.
Hey, this is Jerry Bruckheimer we're talking about, so perhaps we can forgive the fact that Kangaroo Jack contains an arbitrary plot about gangsters. Here we go: Met Charlie, a beauty shop owner in Brooklyn whose best friend, Lewis, is always getting him into trouble. Charlie's mother is married to a prominent mob boss, and so Charlie is always kind of tied up in mob affairs, which goes with insane health risks. Being the good guys in a half-wit mob flick, of course, they find themselves on the long end of the Brooklyn Mafia and are given a redemption assignment to Australia. Their instructions are simple: One, deliver an envelope to a guy named Mr. Smith. Two, don't open the envelope. Three, don't blow it.
Hilarity, as it is wont to do in movies like this, ensues. In this movie, it's mostly because the two heroes are so stupid, they border on mentally disabled. When the duo gets to Australia, they run into a kangaroo, knocking it out. They mistake the knockout for a killing, find it hilarious, and Lewis puts his lucky jacket onto the kangaroo - with the envelope inside the pocket - so they can pose for pictures with it. The kangaroo wakes up and...
Yeah, this is one of THOSE movies.
Our heroes set off after this ubiquitous kangaroo, getting into all sorts of shenanigans on the way. Eventually word gets back to the boss that they messed up their simple courier task, and so he has to send a couple of his more favored lackeys to "take care" of Charlie and Lewis. They meet a nature girl along the way, try scanning from an airplane, see a mirage of a jeep, and lots of other assorted stuff shoehorned in to prolong the movie.
Prolonging it really, really is, especially once you learn the final twist about just what the envelope contained was going to be used for. Turns out the gangsters were simply setting up an elaborate way to do something that could easily have been done in Brooklyn, which means the whole damn movie was unnecessary and would have ended in about five minutes flat in real life. The kangaroo title character has maybe 15 total minutes of screen time, and he was clearly thrown in just to give the movie the sense of conflict - and really, the entire freaking PLOT - that it needed.
Perhaps I'm being a bit too harsh here since Kangaroo Jack was meant to be a kids' movie. But most of the humor feels a bit mature for that. A lot of the humor that can pass for kids' movie humor still isn't clever enough for anyone to really laugh at it. Most people will get a kick out of Christopher Walken playing the head Mafia honcho, but he has even less screen time than Jack.
And, well, that's really it. This movie takes a what-you-see-is-what-you-get approach, so there are no important allegories I have to go in depth about. Kangaroo Jack is an everyday road trip/buddy movie in which the buddies have to chase a kangaroo because one of them acted like an idiot. Show Kangaroo Jack to the little kids. They might get some kind of amusement out of it, but as the kangaroo in question barely shows up and does nothing more than look cool in Lewis's lucky jacket and sunglasses while running away from a bunch of people, even that is debatable.