AceShowbiz -

Hayden Panettiere has a new look. The "Nashville" actress shows it off when dropping by "Late Show with David Letterman" on Wednesday, August 28. She was all smiles as she posed for photographers outside the Ed Sullivan Theater in New York City.

The former "Heroes" star rocked new blunt bangs and platinum blonde hair. The pint-sized singer/actress wore a mini red-and-blue printed Alexander McQueen dress and a pair of sexy red Saint Laurent ankle heels that matched her cherry red lips.

Before stepping out with her hot banging look, she teased her Twitter followers with a selfie that was enough to give a hint at her new do without giving away too much. "My friend said to go look at myself in the mirror...guess ill hafta trust her opinion," she wrote.

"You look like a summer vacation," David Letterman praised the "Wake Up Call" singer's vibrant appearance. "I look like stained glass," she joked.

During the interview, she recounted her recent vacation with rumored fiance Wladimir Klitschko. She joked, "They're really safe with a 110 pound girl on it, but when you add a 245 pound Ukranian on the back it doesn't go so well," referring to the boxer's huge body.

"This thing started sinking!" she recalled. "I got so mad. I got so scared that I got mad at him . . . The water started coming over the edge. I was like, 'This is illegal!' "