The film isn't a disaster by any means. It has a quick, funny start, followed by an intermittently hilarious middle. But the air goes out of the movie as it progresses, and it eventually goes flat. Too bad, because Reilly is an actor who deserves top billing, and he puts everything into the part.
Reilly plays Dewey Cox, who, as a young boy, accidentally kills his brother in a good-natured machete fight. With the hatred of his father behind him ("The wrong kid died!"), Dewey picks up a guitar, plays the blues and eventually finds himself singing at a high school talent show at age 14. (Dewey at that age is played by Reilly--one of the film's decent early jokes.) At 15, he gets married to his 12-year old girlfriend (Kristen Wiig, one of the world's funniest women) and starts having babies.
His job as a janitor in a blues club eventually nets him a singing gig when one of the regulars goes down with an injury. Some Jewish record executives (Hasidic Jews, one of them being Harold Ramis) like what they hear and give Dewey the chance to record an album. Dewey records Walk Hard and finds himself on the rocket-jet-propelled thing to stardom.
Obviously, the film this parodies most would be Walk the Line, the Johnny Cash story. It also takes some shots at Ray (Dewey loses his sense of smell), Great Balls of Fire! (the 12-year-old girlfriend) and even Dylan documentaries. One of the film's best bits would be the Dylan segment, during which Dewey is accused of sounding like the folk hero. Reilly delivers a Dylan-like song with a dead-on impersonation, helped by scathingly funny lyrics.
While Reilly labors for laughs with a script and directorial style that lets him down as the film progresses, it is Tim Meadows, as Dewey's drummer, Sam, who gets the biggest laughs. In a running gag that never gets tired, Dewey is always entering rooms in which Sam is surrounded by women and taking drugs that get progressively dangerous. Sam always starts off by warning Dewey not to come in, but his warnings sound more like invitations. Meadows has always been a great talent, and it's on display here. I often found myself wishing the movie were about Sam.
While I like Jenna Fischer on TV's The Office, she's not blowing me away at the cinema. Her performance in Blades of Glory was underwhelming, and her work here as love-interest Darlene (essentially the June Carter Cash role) isn't much better. She's not a very charismatic actress, and this role requires somebody with greater comic gifts. Wiig outclasses her for laughs.
A sequence involving the Beatles (with unconventional casting that I won't ruin by disclosing here) gets some big laughs, including a Yellow Submarine cartoon break. But for every successful sequence like that, there are two that fail to catch fire. A Partridge Family interlude is just lame, and a chance to poke fun at Sonny and Cher-type variety shows is wasted (although there is one funny conversation about the Incredible Hulk).
I've seen outtakes and deleted scenes that are funnier than most of the stuff that made it into the movie. I saw a politically incorrect folk song on YouTube sung by Reilly that had me laughing--hard. The whole "Patrick Duffy took a beating!" sequence in the TV commercial is missing.
Maybe Walk Hard took a beating in the editing room, and there's an unrated, uncut DVD on the way that will right the wrong.