TORONTO -- Sandra Bullock says acting in the mind-blowing 3D space thriller Gravity was "more like being a part of Cirque du soleil" than acting in a regular film.
Directed by Alfonso Cuarón, Gravity features Bullock and George Clooney as astronauts lost in space after an accident.
Its eye-popping special effects are drawing raves from critics at the Toronto International Film Festival.
At a news conference Monday, Bullock ticked off a list of bizarre contraptions that were used to create the stunning illusion of weightlessness in the film.
She cited an office chair on a hydraulic lift, a wire system that allowed actors to be manipulated by puppeteers and a bicycle seat on a pole.
"We had advisers from Guantanamo," joked Cuarón of the uncomfortable positions and long takes he made his actors endure.
Cuaron said the film presented multiple challenges, including shooting the actors while they were constantly moving.
"There was a lot of careful planning and calculating," he said. "First with the choreography, but (also) ... with how we were going to shoot it. That was the biggest nightmare, because there was no technology... so we had to invent our new set of tools."
Oscar winner Bullock, who is in every scene of Gravity, clearly relished the challenge.
"It was frustrating and lonely and bizarre and you had to sort of dig deep into your imagination and pray that something came up," said.
"But I loved it. I loved that I got to do it and no one had done it before. "
Gravity hits theatres next month.
-- The Canadian Press