The story is familiar. Steve Martin plays Neal, a Chicago advertising man, sleek in impeccable blues and grays, smooth-shaven, recently barbered, reeking of self-confidence, prosperity and anal-retentiveness. John Candy plays Del, a traveling salesman from Chicago who sells shower curtain rings ("the best in the world"). He is very tall, very large, and covered in layers of mismatched shirts, sweaters, vests, sport coats and parkas. His bristly little mustache looks like it was stuck on crooked just before his entrance; his bow tie is also askew.

Both of these men are in Manhattan two days before Thanksgiving, and both want to get home for the holidays. Fate joins their destinies. Together they will endure every indignity that modern travel can inflict on its victims. What will torture them even more is being trapped in each other's company. Del wants only to please. Neal wants only to be left alone.

John Hughes, who wrote, directed and produced the film, is one of the most prolific filmmakers of the last 25 years. He is not often cited for greatness, although some of his titles, like "The Breakfast Club," "Weird Science," "Ferris Bueller's Day Off" and "Home Alone," have fervent admirers. What can be said for him is that he usually produces a real story about people he has clear ideas about; his many teenage comedies, for example, are miles more inventive than the recent sex-and-prom sagas. The buried story engine of "Planes, Trains and Automobiles" is not slowly growing friendship or odd-couple hostility (devices a lesser film might have employed), but empathy. It is about understanding how the other guy feels.

Del, we feel, was born with empathy. He instinctively identifies with Neal's problems. He is genuinely sorry to learn he stole his cab. He is quick to offer help when their flight is diverted to Wichita, Kan., and there are no hotel rooms available. Neal, on the other hand, depends on his credit cards and self-reliance. He wants to make his own plans, book his own room, rent his own car. He spends the movie trying to peel off from Del, and failing; Del spends the movie having his feelings hurt and then coming through for Neal anyway.