Gwyneth Paltrow attends the premiere of Walt Disney Pictures' "Iron Man 3" at the El Capitan Theatre on April 24, 2013 in Hollywood, California. Credit: David Livingston/Getty Images

Gwyneth Paltrow went commando when she walked the red carpet in an Antonio Berardi dress at the Iron Man 3 premiere at the El Capitan Theatre in Hollywood Apr. 24. According to the Oscar winner, the risque gown -- which featured sheer panels on the side -- was a last-minute decision.

"I kind of had a disaster. I was doing a show and I changed there and I went I couldn't wear underwear. I don't think I can tell this story on TV," the 40-year-old said on The Ellen DeGeneres Show Apr. 26. "Well, let's just say everyone went scrambling for a razor."

Paltrow said she was "humiliated" by the bad press the garment generated. A curious DeGeneres then asked, "It was just the side of your leg. . .What is going on with you?"

"I work a '70s vibe," Paltrow said coyly. "You know what I mean?"

The Goop goddess was also asked about her daring look during an Apr. 25 appearance on The Tonight Show With Jay Leno. "There was no underwear on in that dress. Yeah, how does that. . .I don't know," the flustered mother of two said. "I just sort of put it on and it stayed in place, thank goodness."