Extreme Makeover meets Fear Factor!

As the Evil Queen and stepmother to gorgeous Snow White (Lily Collins) in family fantasy Mirror Mirror (out March 30), Julia Roberts plays an aging diva hellbent on staying young and beautiful.

To that end, the fairy tale villainess (with the help of a gleeful handmaiden played by actress Mare Winnigham) subjects herself to a super-duper deluxe -- and disgusting! -- beauty treatment which involves fresh bird poop on her face, maggots in her ear, bumblebees on her lips, and even the sting of  a scorpion.

"Try not to enjoy this," Roberts, 44, snipes to Winningham as the gross-out "treatment" begins.

Watch America's Sweetheart Roberts undergo the grossest beauty regime ever in this exclusive clip!