By Chad Schlegel
Updated January 09, 2009 at 05:30 PM EST

I first became (painfully) aware of Toni Collette’s ability to shape-shift into various roles years ago, when I bet a friend $25 that there was no! possible! way! that the girl who played chubby Aussie teen Mariel/Muriel in Muriel’s Wedding was the woman who starred as Haley Joel Osment’s frazzled Philly mom in The Sixth Sense.

So it would seem that Collette would be the perfect choice to play Tara, a housewife with an acute case of dissociative identity disorder (a.k.a. multiple personality disorder) in the new Showtime series United States of Tara. Tara’s “alters” — prim ’50s housewife, gum-snapping teen, beer-guzzling good ol’ boy — are broad caricatures, really. But smart writing and nuanced performances from the supporting cast — John Corbett (Sex and the City) as Tara’s long-suffering husband, Rosemarie DeWitt (Rachel Getting Married) as her shifty sister, and Brie Larson and Keir Gilchrist as her beleaguered teenaged kids — elevate the proceedings above Tracey-Ullman-in-a-funny-wig territory.

The series — which was created and co-executive produced by EW contributor Diablo Cody (Juno) — debuts on Jan. 18, but you can (and should) watch the first episode below and let us what you think.