A terrible confession: I've never cared for A Prairie Home Companion on America's National Public Radio. No matter how many friends and family tune in to Garrison Keillor's semi-ironic cracker-barrel hour, I've just never found the good people of Lake Wobegone companionable. As much as I appreciate what Keillor is doing (he has, after all, pretty much saved American radio from being completely consumed with Top 40 spin-cycles and mindless talk shows), it is not enough.

Director Robert Altman is, however, someone whose work I do admire. Some of Altman's films, such as McCabe and Mrs. Miller, Three Women and Nashville, are at the top of my favorite films list. The news that Altman was taking on Keillor country was confounding, but promising. It seemed possible that this great cinematic ironist could create another Nashville, using Keillor's small Midwestern town that is as archetypically American and insular as the home of the Grand Ol' Opry to assess the state of the Union.

The union between Altman and Keillor will probably bring cheer to the program's avid listeners. But for those who aren't fans, the film is unbearably slow and thin, more reminiscent of one of Altman's worst films, A Wedding. The set-up is promising, and there are some good performances scattered about. But Keillor's script is unleavened corn pone, complete with a guardian angel of death and a corporate boss threatening to close down the radio show.

It's the last broadcast of Prairie Home, and the old troupers who have joined Keillor (playing himself as G.K.) on stage for over the past 30 years try to come to terms with the show's demise. There are the singin' trail bums Dusty and Lefty (Woody Harrelson and John C. Reilly), crusty crooner Chuck Akers (L.Q. Jones) and the Johnson Sisters, Yolanda and Rhonda (Meryl Streep and Lily Tomlin). Lost among the stars are also real program regulars Tom Keith and Jearlyn Steele.

The film splits its time between the performances onstage, and the characters' interactions backstage. The heartfelt balladry and buffoonery mikeside (complete with Keillor's sketch commercials for Powder Milk Biscuits and The American Duct Tape Council) contrasts with the nostalgic, wakelike recollections being swapped in the dressing rooms. Death seems to hang over the entire theater and, in fact, finally appears in the form of a rather vacuous blonde in a white raincoat (Virginia Madsen), whom ace detective Guy Noir (Kevin Kline as the Keillor creation) tracks with a watchful eye.

The head of the faceless Texas corporation that is suspending operations at the F. Scott Fitzgerald Theater (Tommy-Lee Jones, whom everyone refers to as "Axeman") arrives to take in the final moments of the show. Will someone be able to convince Ms. Death to pay a visit to his private box?

The highlight of the film is Streep and Tomlin's double-act. Although they valiantly struggle to sound like natives of Oshkosh or Nashwauk (Streep loves nothing more than "playing the neighborhood"), the two actresses work extremely well together. What this film and Nashville share (other than the basic framework of life on and off stage) is Altman's knack for turning actors not known for their musical talent into musicians. Streep and Tomlin (who is the lone Nashville alumnus here) prove to be excellent singers, while Harrelson and Reilly pick and strum their way effortlessly through their own songs. Altman also insisted that the film be shot before a live audience, which gives it that extra verisimilitude.

Keillor is Keillor, of course, making sure that he has the best lines (and there are a few memorable ones). But too much of his plot hinges on inept conventions. The Guy Noir routine is exhausting. Parodying (if not parroting) Chandler and Spillane hasn't been clever since Vincent Minnelli's great Band Wagon, and Kline's debonair slapstick shtick has become boring.

The Philistine Texan Baptist who comes to town to close the show is obviously modeled on certain political personages, and there is something uncomfortably true to life in such a creature being the one to have the F. Scott Fitzgerald Theater bulldozed. Still, it's a vein that Keillor doesn't quite sufficiently mine.