Actress Sigourney Weaver says she is now scuba certified after taking a crash course in free diving for shooting filmmaker James Camerons upcoming Avatar sequels.

Weaver will be seen playing a new character in the upcoming sequels following the demise of Grace Augustine — her role in Avatar.

To prepare for filming in the big tank next month, the 68-year-old actress took a crash course in free diving, reports

“I’m now scuba certified as well as in the midst of becoming an accomplished free diver,” Weaver said.

“Once I completed my scuba course, Jim (Cameron) said to me, ‘The 75 per cent of the world that’s underwater is now part of what your world gets to be’.

“We’re going to have to do long takes underwater, and we won’t be wearing scuba gear because we’ll just be our characters, swimming,” she added.