Katherine Heigl -- Rocked Up!

1/3/2008 11:06 AM PST
Katherine Heigl is a big fat liar -- and she's got the huge bling to prove it!

TMZ caught the newly married "Grey's Anatomy" star on Robertson Blvd. in Los Angeles yesterday, showing off her wedding ring to the snapping paps. She called it "simple" -- we call that a gross understatement.

Watch the video to see her new rock -- and decide for yourself.