It's not just cheaters that bring out Carrie Underwood's nasty side.
At the November 10 CMA Awards, a super-anxious Leighton Meester, 24, was prepping backstage to present an award when the 27-year-old American Idol champ, who was co-hosting the show with Brad Paisley, approached her and said, "Get out there and don't f--k it up," reveals a source. "It made Leighton more nervous."
To find out what prompted the tough love taunt -- and Underwood’s views on the cutthroat industry — watch the latest Hot Stuff video (above).
Also inside the sizzling round-up, as told by Senior Editor Ian Drew: how Christina Aguilera met new beau Matthew Rutler's folks; who Eva Longoria spent the Thanksgiving holiday with; why Teen Mom's Amber Portwood was reunited with her two-year-old daughter Leah and more!