There's a Neil Young song placement in Due Date that, if you're not careful, will smack you right across the face. You'll look up, surprised, and wonder why, precisely, Todd Phillips would make such a choice. It's just brutal, it skews the tone, and it makes the film tough to take seriously afterward. Which wouldn't be such a bad thing if this film was an attempt at hilarity, as all the early indicators point to. But this isn't a true comedy. It's either a drama that's not serious or believable, or a comedy that's not funny enough. Either way, we're looking at a very "bad times" situation.
The story draws heavily from road trip films, and Plains, Trains, and Automobiles should be listed in each and every review, except this one!
Plugging onward, gifted character actor Robert Downey Jr. is a man desperate to get home in time for the birth of his son. Zach Galifianakis is a fellow traveler. They've never met, and they immediately commence with the awkward and contentious banter. Through a (somewhat logical) chain of events the boys are forced to travel together, from Atlanta to Los Angeles by way of rental car, and we're privy to all the petty squabbles and poor communication the script can muster.
Now then, the impetus for the trip is logical, but many of the events surrounding the rest of the film aren't. There are a few drug-related moments that don't add up. There's a "fight the man!" scene that borders on being a Hunter S. Thompson essay. But I suppose we owe it to posterity to at least attempt a cursory look at the characters portrayed by ZaGa and RoDo. Galifianakis is as earnest as they come, almost to the point of complete unawareness as to how the world works. He's the foil to Downey's plans to get home fast, without delay, and in a manner that doesn't involve introspection or bonding. Downey is a hard-charging architect (total stereotype, amiright?) who is forced to deal with Ethan (Galifianakis) because he lacks his wallet, and the items found within (identification, money, credit cards).
Along the way we learn that Ethan is struggling with some personal setbacks, and that Peter (Downey Jr.) may not be the most pleasant fellow. But the film desperately lacks the "put the laughs in front" aspect of The Hangover. These are difficult characters to care about because one is from Mars and the other one often displays meanness. You might naturally take Peter's side in most of the altercations, because Ethan is an idiot, but then you figure out he's a sweet and well-intentioned idiot -- which makes it hard to take any side at all. But you're definitely not laughing or learning throughout, and films like Get Him to the Greek have already done a far superior job with madcap this year.