It's easy to forget while watching the explosive action sequences of a James Bond movie that it is actually the product of months of day-in, day-out work on the part of hundreds of people, who do it for a living. One of those lucky few is stunt coordinator Gary Powell.

Powell is sort of a legacy when it comes to stunt work for the Bond series. He doubled for Pierce Brosnan, while his brother, Greg, doubled for Roger Moore and Timothy Dalton. Long before that, his father and uncle doubled for Sean Connery.

"Skyfall" marks Powell's third film as stunt coordinator for the series, so we turned to him to break down the challenges of five of the latest Bond movie's most thrilling sequences.

(Minor spoilers ahead.)

The Opening Chase

The basic premise of the chase, which finds Bond following a killer in a car, then a bike, then a train, was included in the script, according to Powell, but that was only the beginning. The most elaborate stunts from the sequences, like Bond's dash across the arm of a digger, came later.

Though it may be hard to believe, Daniel Craig did many of the stunts himself. "Obviously, [Craig] was there a lot. We had a second unit in Turkey shooting a lot of stuff with the doubles," Powell said. "Then Sam and Daniel come over towards the end, and then we did a few weeks with them and put him everywhere. He was in the car, did a lot of riding on the motor bike, obviously a lot of stuff on the train roof, getting into the digger, running across the digger, the fight stuff on the big bridge."

And unlike previous entries, during the Brosnan years especially, there was no major CGI used. "Everything you see in that was all real people," Powell said.

The Skyscraper Fight

Once on the trail of Javier Bardem's Silva, Bond travels to Macau to find him and the killer from the opening sequence, eventually finding him in a glass-filled skyscraper. The biggest challenge for Powell's team, besides keeping the camera out of the many reflections, was making a nearly one-take fight look exciting but unrehearsed. "It was messy, not too perfect. If you rehearse too much, it can get very robotic," he said. "The challenge is to make sure it looks fresh, as if it was two people fighting to the death sort of thing."

The Macau Casino

After getting some key information in a lavish casino, 007 must fight off a group of henchmen and eventually ends up falling into a Komodo dragon pit. The scene is obviously thrilling but also funny, thanks to some acting choices on the part of Craig, something that's taken into account when planning the fight. "When we start blocking out the fights, we get [the actors] in there and start going through it, and we want their input, because Daniel's going to play Bond how he plays Bond," Powell said. "He's the best person to tell us what he might be doing. A classic example is when he jumps off the digger and lands, he adjusts his cuff link. That was something [Craig] came up with."

The Tube Chase

Part of what makes "Skyfall" distinctive as a Bond movie is that it takes place largely in the U.K. When the location was decided, Powell and the creators of the film wanted to take every advantage they could when it came to filming their native country, and that meant using the London Underground. "We're in London; let's use the Underground -- and we did," Powell said. "Ask anyone in London, and they'll tell you they've wanted to do a slide down the escalators. We got a chance to do that."

The Finale

Without giving too much away about the final battle of the film, it involves a cameo from the most famous of all Bond cars, the Aston Martin DB5. During filming, Powell and Craig were able to take the iconic car out for a spin, much to the surprise of anyone who saw them. "It was just surreal driving down the road, and James Bond's driving this DB5 and you just see the looks on people's faces. 'Aw, freaking hell. Someone's driving a car that looks like Daniel Craig.' It was brilliant."

Check out everything we've got on "Skyfall."