LOL! SOMETIMES ACTOR'S NEED TO STAY IN THEIR OWN LANE!

If you can act, you can sing.
At least that's how movie and stage directors must look at it.

How else to explain how a pitch-impaired Pierce Brosnan got to bellow some ABBA songs in the movie version of "Mama Mia"? Or why Chihauhau-voiced Melanie Griffith found herself, at one point, cast in the Broadway company of "Chicago" - in the lead, no less.

There's a long, rich, and sometimes painful, history of non-singing thespians crooning their hearts out on stage and screen, one which, in the best case scenario, snakes back to the sublimely droll Rex Harrison in "My Fair Lady."

Since musicals have to function as theater, before they pass as something like concerts, it makes sense that any star blessed with presence, diction, and character could potentially convince an audience that they're at least functional as chanteurs.

After all, that's what actors do - make you believe they're something they're not.

But never has this point been pushed to the giddy zenith of the movie soundtrack to the musical "Nine."

The just released CD may just feature more stars not primarily known for singing than any disc in history - no fewer than 7 - including Daniel Day Lewis, Kate Hudson, Nicole Kidman, Marion Cotillard, Sophia Loren, Penelope Cruz, and dame Judi Dench (who risks losing that title simply by appearing).

The only star in the whole shebang who's known first for her mike work is The Black Eyed Peas' Fergie, who in a classic bait-and-switch move, gets to croon the CD's lead single, "Be Italian."

Otherwise, the album promises to serve up one candidate for David Letterman's joke record collection after another.

Unfortunately, it delivers in spades. To make up for the stars' inability to sustain their voices in song, they all act up a storm, over-articulating every phrase, and so, overselling every point.

The result makes the already arch music by Maury Yeston seem even starchier.

Daniel Day Lewis, who plays a Fellini-like Italian director, attacks his songs with such a stereotypical accent, he sounds like Father Guido Sarduchi from "Saturday Night Live." Kate Hudson, known more for her cutes than her crooning, means to vamp sexily through "Cinema Italiano," but there's no sensuality to her tone. For their parts, Loren and Dench mainly speak their songs with flair, in the hope that nobody notices they're not really singing.

Of course, a generous use of echo, and a heavy reliance on pitch correctors, helps all the stars avoid coming off like William Shatner. But when you hear Fergie belt out a bonus track not featured in the original show ("Quando Quando Quando"), or when you listen to the Noisettes romp through the period piece "IO Bacio . . . Tu Baci," you hear not only what's missing from the non-pros but from Yeston's stiff score itself.

Unfortunately, in the end all the studio tricks that aid the stars do the listener no favors. They merely prevent "Nine" from becoming howlingly bad enough to rate as camp. Instead what we get is just one long stretch of dull, driving home the point that just because you can make a character come alive, doesn't mean you can make one sing.