Penelope Cruz says pretending to be someone else is "like a drug".

The 'Broken Embraces' star spent her childhood impersonating people she met in her mother's beauty parlour because she was "hooked" on the rush it gave her.

The 35-year-old actress said: "I would play with my girlfriends, pretending to be somebody else and I started to notice that that feeling was like a drug for me.

"My mother's beauty salon was the best acting school for me. I don't know why, but women in a hair salon share their deepest secrets. I was 11 and I would sit there and pretend I was doing my homework but actually I was observing all of those women."

Since then, Penelope has made a name for herself playing unpredictable characters but being so emotional on screen takes its toll on the actress.

She explained: "I always feel scared and insecure on a film set. I don't know any other way. Most of the hours you spend on set you are actually trying to hold on to the emotions of your character.

"Sometimes you will do a close up where you are totally distraught, then shoot the rest of that scene seven hours later. How do you hang on to that feeling all day without burning up, without going so far you've got nothing let to give when the cameras roll again. That's a little bit like playing with fire."