Naomi Watts: 'The Impossible' tsunami felt all too real

Oscar buzz is swirling round Naomi Watts for her gritty performance in "The Impossible." The film follows the harrowing, true-life tale of a vacationing couple (Watts and Ewan McGregor) and their three young boys who were swept up -- and separated -- during the 2004 tsunami that struck in the Indian Ocean.

The movie hit Long Island theaters last week, and may especially resonate here, given our recent dose of Mother Nature in the form of superstorm Sandy.

"We got a glimpse into how powerful nature can be," says Watts, who was raised in England and Australia and now lives in New York with her partner, Liev Schreiber, and their two sons.

Watts was recently nominated for a Golden Globe Award for "Impossible," which was shot on location in Thailand and in a massive water tank in Spain.

Arriving at the airport in Phuket, Thailand, was "intense," she recalls.

So much still needed to be repaired, and "everywhere you went, people wanted to share their experiences of loss or survival."

It took an entire year for Spanish director J.A. Bayona and his special effects team to create the 10-minute tidal wave sequence, which required some 100 shots and moving more than 35,000 gallons of water each day in a tank the size of one-and-a-half football fields.

The overall effect is visceral, as Watts and Tom Holland -- a young British actor who plays her eldest son -- appear to be dragged and pulled under water by roiling currents, thrashed and impaled as human bodies, tree branches, cars, buildings and debris all swirl together in a maddening rush.

Watts and Holland spent six weeks in the tank, strapped into giant flower-pot-like contraptions and pulled along tracks, submerged to their chins amid waves and debris.

"We were gasping for air, spitting out water... it created a level of fear that was... was real," says Watts. "Whenever I thought, 'I don't know if I can do this again,' you just remember this was nothing compared to what people actually went through."

The filmmakers felt compelled to make the scenes appear as realistic as possible, and digital effects on a green screen wouldn't do.

"It was exhausting, definitely the hardest physical thing I've ever done," says Watts.

"Tom thought it was like a water park; he loved it," she says, chuckling. "But he's 14."