Due Date aims the slow burn of Robert Downey Jr. at the addled idiocy of Zach Galifianakis in a Hangover director's version of Planes, Trains and Automobiles. And shockingly, it's funny. Often in shocking or at least wildly inappropriate ways.
The setup: Peter, a harried businessman (Downey) dashes to the Atlanta airport so he can be home when his wife (Michelle Monaghan) gives birth. Her "due date" is Friday. But Peter runs afoul of Ethan (Galifianakis), a shambling bear of a boob, traveling with a pug dog named Sonny. From the instant Ethan's pal smashes his car into Peter's Town Car limo, the chubby guy is bad news.
"We haven't been drinking." Pause. "We split a six pack." Pause. "Of 40s."
Before Peter can say "Get me a restraining order," Ethan has had him shot by an air marshal ("Relax. It's just a rubber bullet."), kicked off the plane and put on the international "no fly" list. Peter's wallet is in transit, and he is trapped in a Subaru Impreza dawdling cross-country with a chatty dope who smokes dope ("Glaucoma." Right.), and who is headed to Peter's home, Los Angeles, because he thinks he can be an actor. On TV's Two and a Half Men, no less.
The stupid stacks up with the stunning as this odd couple endure wrecks, border crossings, visits to pot dealers (Juliette Lewis steals her scene) and an irate war-vet Western Union clerk (Danny McBride). Dealing with the man-child Ethan should convince the hot-tempered Peter that he's not ready for fatherhood, and dealing with blunt, sarcastic and menacing Peter should convince Ethan that he's not ready for Hollywood. Not that we're going to have a lot of "growing" or "learning" here. The best either man can promise about his shortcomings is "I'm working on it."
This "Hangover Hits the Highway" benefits from what one can only assume is a lot of riffing by the cast — one-liners topping other one-liners. Bit players Lewis and Jamie Foxx pitch in. Downey unloads, "I despise who you are at a cellular level." And Galifianakis makes Ethan another poster man-child for Hipster Doofus.
He quotes Ice Cube the rapper, not the family road-trip movie actor he became: "You'd better check yourself before you wreck yourself."
Todd Phillips' film takes a couple of sentimental detours, and not every cameo pays off with big laughs. Upping the ante at every state line becomes a challenge that rivals explaining how Mike Tyson's tiger got into that hotel suite in The Hangover.
But it's a streamlined movie, with just two very funny actors carrying the laugh load. Galifianakis is every bit as nasty and gross as he was in his breakthrough film with Phillips. And he has added a swishy side to his Hangover bag of tricks. His performance and Downey's reaction to him combine for a Due Date that comedy lovers won't want to miss.