The first three films were famous for their plot twists and surprise endings, and by the looks of it, the next instalment will be no different.

Courteney Cox was photographed on the set of Scream 4 clutching the famous ghost mask worn by her former nemesis, the killer.This has led to speculation that she might be switching sides in this film, and donning the costume that has terrified audiences for more than a decade.
Courteney’s character, news reporter Gale Weathers, could also have just found the mask discarded, and is being chased herself.Either way, fans will have to wait until the film’s release in April 2011 to find out.

On location on a remote farm outside Detroit, Courteney, 46, looked a little nervous to be standing amongst the dark forest, despite being surrounded by film crew.The actress was wearing a casual outfit of leather jacket, black jeans and boots, suggesting she will be filming a a chase scene.Whether she will be the pursuer or pursued remains to be seen.

Earlier that day, a barn t the location was set up to look like a typical horror scene from the film franchise, with ’scarecrows’ wearing the killer’s outfit of ghost mask and cape erected around the premises with bloodied knives attached.

The entire cast have been hard at work, filming every day in several locations around Michigan.Courteney was photographed in a more glamorous outfit on set earlier this week, looking immaculate in a tight purple dress and matching heels.Her husband David Arquette, as well as new cast members Hayden Panettiere, Emma Roberts and Adam Brody have also been spotted shooting scenes for the film.

Cox has ensured that she won’t be outshone by her younger co-stars, and revealed to the August issue of US InStyle magazine that she uses Botox to stay fresh.

‘Aging gracefully is one thing, but trying to slow it down is another. Sometimes I use Botox. Compared to most, I use it very sparingly.’

The actress admitted to going overboard in the past.

She said, ‘I feel weird if I can’t move my face, and that one time I overdid it, I felt trapped in my own skin.’