KILL BILL star Daryl Hannah is spending her Christmas holidays in a secret location working on a documentary exposing human trafficking.

The statuesque actress, who prides herself on living an eco-friendly lifestyle, plans to travel to an undisclosed location with cameras in an effort to shine a light on the plight of those caught up in modern-day slavery.

She says, "There are more slaves now than at any other time in human history. There are 30 million slaves in the world right now. Many of them are slaves in the labour field, but 75 per cent of them are in the sex trade and of those 75 per cent, which are women, most of them are the age of 18.

"So I'm going to go over there and me and a friend of mine are going to go undercover. We're going to dress like a twisted couple and go into these brothels and things.

"My friend actually rescues slaves. He actually busts them out and rescues them. I have some disguises but I can't reveal what they are.

"Unfortunately, it's real and it's really, really sad. I went over to some of these countries in August and did some filming."