Early on, downtrodden corporate drone Todd Woods (Paul Giamatti) is coaxed by a pretty girl to sing "Hello It's Me" in a hotel bar, and after an unsteady start, he turns the number into a strutting tour de force. He's vocally dreadful, but he performs with such relish, such delighted amazement at his own lack of inhibition, that the crowd (onscreen and off) goes nuts for him. The point isn't vocal perfection, any more than the point of poetry slams is to create Petrarchan verse. Rather, it's to take the right to entertain back from the slickly produced professionals. The revolt against the homogenization of culture is a theme that's tough to bring off without sentimentality, but it turns out to be the most touching element of Duets.
Each of the film's pairs neatly consists of one character in need of redemption and one ministering angel. Angel No. 1 is the pointedly named Liv, a guileless Vegas showgirl who meets her father for the first time at her mother's funeral and gloms on to him at once, determined to bond. The father, played by '80s pop dreamboat Huey Lewis, is a professional hustler who empties wallets with killer Joe Cocker covers. Liv is played by Gwyneth Paltrow -- and yes, it turns out that Miss Thing can sing pretty well, too.
Angel No. 2 is Billy (Scott Speedman), a guileless Cincinnati underachiever who drives a cab. On the rebound from an unfaithful girlfriend, he stumbles into the company of Suzi (Maria Bello), a trampy itinerant bombshell who earns her keep with sex when she doesn't win enough in karaoke contests. Billy started out to be a priest, and, you guessed it, he teaches Suzi to respect herself.
The wild card is the strand involving Giamatti as the sad-sack company man Todd, who cracks one day under the strain of anonymous, generic business travel, leaves his suburban home and family, and just keeps going, wandering from karaoke bar to karaoke bar, popping pills, drinking beer, and driving recklessly. Along the way he picks up Angel No. 3, an armed convict named Reggie (Andre Braugher) with a glorious singing voice. The two sing a heavenly "Try a Little Tenderness" together in a redneck bar. Inseparable thereafter, they head for a big-purse karaoke contest in Omaha, where the three plotlines converge at the melodramatic climax.