Tom Cruise Preps for 'MI 4'

At 49 years old, Tom Cruise takes care of his own death-defying stunts in the upcoming Mission: Impossible - Ghost Protocol. The seasoned action star spoke about what he did to prepare for the role and why he took it on in the first place.

"What they did first is they actually built walls for me just to practice my climbing," said the Golden Globe winner, who explained that he did drills scaling these practice walls as fast as he could to build up his endurance.

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The model walls were meant to replicate those of Dubai's Burj Khalifa, the tallest building in the world. In the film it's Cruise himself, not a stunt double, who dangles from the side of the building that stands at 2,716 feet!

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"I love making these movies," said Cruise, explaining why he would take such risks this late in his career. "I enjoy the challenge of coming up with these sequences."

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In the newest installment of the Mission: Impossible franchise, IMF operative Ethan Hunt (Cruise) is blamed for the terrorist bombing of the Kremlin. He is then disowned along with the rest of the agency when the President initiates "Ghost Protocol".

Left without any resources or backup, Ethan must find a way to clear his agency's name and prevent another attack. To make matters even more complicated, Ethan is forced to embark on this mission with a team of fellow IMF fugitives whose personal motives are unknown.

Mission: Impossible - Ghost Protocol hits theaters December 21.