Clooney, Bullock launch Venice into orbit with "Gravity"

STORY: The 70th Venice Film Festival kicked off to an explosive start on Wednesday (August 28), with the premiere of Mexican director Alfonso Cuaron's 3D space movie "Gravity," which opened the festival and runs out of competition.

The film stars George Clooney and Sandra Bullock as astronauts and the actors walked the red carpet to cheering fans.

In "Gravity," their shuttle is destroyed by an avalanche of space debris triggered by a botched Russian missile strike.

The film was a physical and emotional challenge to both actors as their characters are lost in space fighting for survival.

They embark on a roller-coaster ride from hell to get back to earth.

Twenty films, including five from the United States and three British ones, are in competition for the Golden Lion trophy that will be awarded at the end of the world's oldest film festival on Sept. 7.