James Cameron is one very busy man: while officially gearing up to shoot Battle Angel, his 3D movie adaptation of the popular Japanese manga series, it has emerged that he is also developing a parallel 3D project, a sequel to 1994's True Lies and an underwater adventure about freediving.

Battle Angel is based on Yukito Kishiro's 12 graphic novels about a cyborg girl who tries to recover her true self while fighting the forces of evil in a gigantic and mysterious mid-air city.

Sources at Cameron's Lightstorm Entertainment told the Hollywood Reporter that in tandem with Battle Angel, Cameron is planning a parallel project, currently called Project 880. Both films are to be shot with custom-designed high-definition cameras and will use a version of the performance capture technology used by Robert Zemeckis on The Polar Express.

In addition, the director is also hard at work on a sequel to True Lies, the hit action flick that starred Arnold Schwarzenegger and Jamie Lee Curtis. Cameron's fourth project on the go would return the Titanic and Ghosts of the Abyss director to his fascination with the deep. Called The Dive, it is based on a Sports Illustrated story about freediver Francisco Ferreras and his wife Audrey Mestre, who died while trying to break her own depth record.