Pamela Anderson has long held the enviable status of being one of the world's most desirable women.

But everyone has bad days, and yesterday the former Baywatch star went for a stroll in New York's Central Park with her 10-year-old son Dylan and a mystery man looking worn-out and uncharacteristically dowdy.

The 41-year-old may not have been looking her best but, proving she still knows how to accessorise, was carrying a designer bag.

A tale of two Pamelas: Anderson looked tired during a visit to New York's Central Park (left) but was back to her glamorous best later that night (right)

However, just hours later and Pamela had undergone a complete turnaround.

Arriving to film an appearance on The David Letterman Show, the mother-of-two looked stunning in a tight white dress that showed off her best-known assets.

Earlier this month, Pamela enjoyed a two-hour stint on Australia's Big Brother reality TV show.

Pamela looks like a typically tired mother in Central Park (left) but stepped out for an interview on David Letterman's chat show ever the professional (right)

Despite being paid a reported £245,000 for her guest appearance on the KFC-sponsored show, the star took part in a People for the Ethical Treatment of Animals (PETA) protest against the fast-food eatery just one day later.

Vegan animal rights campaigner Pamela took to the streets with fellow protesters demanding the fried chicken giants implement better guidelines for treating the birds.

She said she was unaware the chain was partially funding the reality show prior to signing up.

Glowing: Pamela signed autographs for fans outside The David Letterman Show's studio in New York

Day out: Pamela Anderson walked though Central Park with a mystery man while her son Dylan skateboarded nearby