The film version of Herb Gardner's play, I'm Not Rappaport, overcomes these potential difficulties with flying colors. Thanks in part to Gardner's sensitive adaptation, and in part to the talent of his actors, the film retains the delightful blend of humor and pathos that earned the stage version a Tony Award. Far more than being just a passable cinematic version, I'm Not Rappaport turns out to be funny and charming -- A Grumpy Old Men with soul.

The film follows the adventures and misadventures of Nat (Walter Matthau) and Midge (Ossie Davis), two old geezers who spend much of their time occupying opposite ends of a bench in New York's Central Park, not to mention completely opposite views on how they should go about living through their twilight years. Nat seems to have taken Dylan Thomas's imperative -- "Do not go gentle into that goodnight" -- to heart. He is a romantic, a wag, a pot-smoking, wisecracking dreamer, and a master of Walter Mitty-like self-invention. All the things that old people aren't meant to be. Midge, on the other hand, seems content to sit and read his paper, to go quietly about his business with as little fuss as possible, to live out the rest of his days in peace and obscurity. But with the hell-raising Nat around, there's little hope of that.

The less-than-dynamic duo play off each other marvelously. As well as refusing to submit to the present, Nat also refuses to relinquish the past. Holding on to unfashionable ideals of social justice, he crusades for the rights of workers, consumers, and anybody else he sees as a victim -- whether they want him to or not. As the main beneficiary (or victim) of Nat's extravagant efforts to secure justice for one and all -- and as the target audience for many of Nat's outlandish fabrications -- Midge is driven to distraction, and even ineffectual violence, by his friend.

Matthau is adorable, making full use of his doughy charm and impeccable comic timing to make Nat both irresistible and infuriating. His character is also, it turns out, surprisingly wise. When berated by Midge for his constant lying, Nat says, "They're not lies, they're alterations. Sometimes the truth don't fit. I take in a little here, I let out a little there, until it fits." Davis, reprising his Broadway role as the shortsighted, curmudgeonly Midge, is the perfect straight man to Matthau's oddball. He endures Nat's antics with a mixture of outrage and resignation -- and, we suspect, a little hidden pleasure, too.

In a perverse way, Nat may even be good for Midge. When the smarmy yuppie Danforth (Boyd Gaines), head of the tenants' committee at the building where Midge is superintendent, attempts to ease Midge out of his job, Nat stands up to him in a way that Midge never could. "You collect old furniture, old cars, old pictures," he fires at the quivering Danforth, "everything but old people. They make bad souvenirs, they talk too much; even quiet they tell you too much. Well, they haven't stayed late to ruin your party." It's the kind of speech that Hollywood usually minces into a slush of sentimentality; here it's effective: touching and right on the mark.

Despite the surface acrimony, and their seeming incompatibility, Nat and Midge are a match made in heaven. In one hilarious scene, they smoke a joint of government-supplied "medicinal" pot and giggle like schoolboys; they sing, they dance, they reminisce. Central Park becomes their playground, a place of magic and music. But the park also plays host to darker forces: predators and thugs who remain impervious to Nat's sleight of mouth, who have the ability, and inclination, to cause the pair great harm.

When Nat and Midge come to the aid of a junkie (Martha Plimpton) who owes money to a vicious drug dealer (Craig T. Nelson), things turn decidedly nasty. Even more of a threat to their lifestyle is Nat's well-meaning daughter Clara (Amy Irving), who is determined to have her father interred in an old-folks home. The trials that they go through strengthen, but also threaten to shatter, the bond that forms between the two friends. Like Tom and Huck, Butch Cassidy and the Sundance Kid, or Batman and Robin, Nat and Midge are an unforgettable twosome. And I'm Not Rappaport is an unforgettable film.