Starring Robert Downey Jr and Zach Galifianakis. Rated PG

Not a maker of high art—entirely to his credit—Todd Phillips is a filmmaker who has concentrated on making eccentric genre comedies, about topics such as road trips (Road Trip), age-inappropriate men indulging in gross-out antics (Old School), and the picaresque absurdism of Zach Galifianakis (The Hangover).

Just in time for the dead space that is the late fall/pre-Christmas season, Phillips returns with Due Date, a mismatched buddy epic that combines elements of roadtripping, grotesque behaviour, and the ingenuous stylings of Zach Galifianakis.

Structurally, the movie is nearly a remake of Planes, Trains and Automobiles, with an uptight businessman forced into a cross-America journey with a wildly incongruous companion who is both the source of and solution to his immediate frustrations. There’s a curious parallel in the casting of a notorious zany (in this case, Robert Downey Jr.) dialling back the mania to play the straight-man figure. RDJ, portraying an expectant father racing home in time for the birth of his child, provides a Cleesian study in repressed rage, all precise enunciation and heroically controlled expressions, the anger seeping out in bursts of startling cruelty immediately followed by regret.

It’s a characteristically mannered RDJ performance, but, as one might deduce from the trailer, Galifianakis is the movie’s star and principal source of humour. The lavish beard and hair make him something of a Muppet, but with his expressive eyes and ineffable anti-charisma—a colloidial suspension of arrogance and haplessness—Galifianakis proves himself a comedy star. With its theme of male bonding and the pressures of fatherhood, Due Date might be in peril of sentimentalism or, worse, a life lesson. But then Phillips has the sense to cut to a masturbating bulldog to keep things zooming in style, if not taste or originality.