We don't know exactly how long she could hold her breath underwater, but she clearly pushed herself to the limit: She repeatedly ruptured an eardrum from the hours she spent in studio tanks.

They went hardcore. The cast was trained to hold their breath for minutes to pull off those mesmerizing underwater shots. No CGI shortcuts—this was the real deal, folks. And the person ...

Kate Winslet has reunited with her "Titanic" director James Cameron for his long-awaited "Avatar" sequel, and the pair are once again spending a lot of time underwater. New images released by the ...