'Tron: Legacy' concept art (images)

"Tron: Legacy" opens in theaters in December, following the first "Tron" film by some 28 years. Disney has released a handful of concept images from the new movie showing characters, vehicles, and props.

Seen here is a mock-up of the new version of the grid city, which features a massive spire. On the top of the mile-high structure is a bar called the "End of the Line" club. Zooming toward it is one of the film's "recognizers"--a vehicle that seeks out rogue programs within the digital world.

Rinzler, played by martial arts guru Anis Cheurfa, can split his data disc in half to use as two weapons.

The "sirens" within the world of "Tron: Legacy" are modeled after those found in Greek mythology.

Jeff Bridges' younger self in the film has his own security force. Seen here is a mock-up of the "lead guard."

According to Disney, Quorra (played by actress Olivia Wilde, pictured right), originally trained for her role in flat shoes and had to retrain for all her stunts in 4-inch heels.

Each actor's helmet was made specially for his or her head. This one, created for Olivia Wilde, was made to within a quarter of an inch of the skin--and sometimes less in places.

Sam Flynn, played by Garret Hedlund, has a helmet comprised of several different materials. Designer Neville Page, who has a background in industrial design, said that while most movie props are made as cheaply as possible, the helmets for "Tron: Legacy" were made using the same materials and techniques used to make car headlights or sports helmets by Nike.

Along with the hard, clear plastic layer, the helmets also integrated the suit's lighting effects.

Tron's iconic lightcycles return in "Tron: Legacy," and bring with them the deadly trail that can cut off other racers who aren't quick enough to steer out of the way. The cycles debuted their new look in a visual-effects test at 2008's Comic-Con.

Unlike lightcycles, the "light runner" seats two, and can go off the grid's power source, letting it drive out into the off-grid area known as "the Outlands."

The reworked version of the lightcycle has been made to more closely blend with the rider, an effect the creators were going for in the first film, but were unable to accomplish due to technological hurdles.

An early sketch of the lightcycle. Designer Daniel Simon quit his job doing automobile design in Germany to work on "Tron: Legacy." Each vehicle he created has a seam that runs through the entire body.

A 3D rendering of the lightcycle from the previous slide, with lighting and ambient reflections.

A top-down view of a lightcycle with a rider atop it. In the new design, the rider is nearly horizontal, and protected on the top with a roll bar of sorts.

A retro version of Jeff Bridges' character Kevin Flynn's lightcycle from "Tron: Legacy." In the previews for the film, you can see it in the living room of his safe house.