Scarlett Johansson filmed undercover in Britain

Scarlett Johansson went undercover in Britain during filming of her new movie Under The Skin so she could shoot scenes with unwitting real life participants.

The Avengers star plays an alien seductress in human form in the sci-fi film, which she shot on location in Scotland, preying on lone male travellers.

Director Jonathan Glazer decided he wanted to include real people and their genuine reactions to Johansson, so the actress interacted with ordinary passers-by who weren't aware they were being filmed for a movie.

However, the blonde beauty admits she felt nervous about the deception, telling reporters at the Toronto International Film Festival in Canada, "That was terrifying initially. The feeling of knowing something no one else knows. Not being able to control a situation. There was lots of pressure. But what made it terrifying also made it liberating."