Naomi Watts

Naomi Watts thought she was going to die while filming a scene that went wrong for 'The Impossible'.

The 44-year-old actress plays a mother who, along with her husband and three children, is caught up in the Indian Ocean Tsunami in December 2004, and she has revealed that art eerily imitated life after a technical hitch left her submerged under water without air.

Speaking to the Metro newspaper, she explained: "Something went wrong technically with the chair they strap you to when they submerge you in the water. It spins you around under water and the crew just weren't able to shut it off at the right point. I couldn't get out and was really struggling for breath."

Naomi - who has two children, Sasha, five, and Sammy, four, with actor Liev Schreiber - insists the incident gave her just a small sense of what people endured in the natural disaster, which claimed 275 000 lives.

She said: "It helps you to imagine. You can get tiny glimpses of what people went through. Though even this incident was nothing compared to what it was really like."

The movie is based on the true story of a Spanish family's experience of the tsunami and Naomi admits meeting the woman whose harrowing tale she retells on-screen was a powerful experience.

The Hollywood star said: "The thing that really surprised me was that she said she felt so connected to her instincts at the time of the disaster and she was so sure about the big decisions she had to make. That was surprising because I can't imagine being so in touch with my instincts.

"I had played a mother a lot of times before I was a mother but now I am a mum, I worry about my own children every day in the tiniest ways. Definitely having been a mother and playing this character, it added a lot of weight to it."