Full of gumption, Clarkson and Guarini soldier on, seemingy unaware that the perfectly adequate singing voices that brought them to the big screen are being drowned out, on a half-dozen same-sounding songs, by an overlayered backup group.

They play cotton candy effigies of themselves named Kelly and Justin, and the best that can be said is that they don't embarrass themselves.

The most resounding thuds in From Justin to Kelly, however, come from the musical numbers.

A feather-light musical rushed into production to capitalize on American Idol-frenzy, is nothing more than an excuse to give the two leads several musical numbers, a la those Frankie Avalon-Annette Funicello "Beach Blanket Bingo" movies, and with just about the same amount of substance, too.

In this frothy beach movie, they make pop-music lite together but create an utterly unconvincing romantic couple, seeming more like siblings or best friends. From Ruben to Clay might work better.