"Sky Captain and the World of Tomorrow" is many things. It is writer/director Kerry Conran's homage to old movies, pulp magazines and Max Fleischer cartoons. It is an experiment in virtual filmmaking. And it is, at times, visually impressive. Unfortunately, it is also the one thing no action/adventure movie should be — breathtakingly dull.

Copyright © Paramount Pictures Gwyneth Paltrow and Jude Law star in ''Sky Captain and the World of Tomorrow.''

"Sky Captain" is set in an alternate universe in which the 1930s was a golden age of super-science and technology. The sky is filled with dirigibles, which dock midair to unload passengers at the top of the Empire State Building. And no one seems particularly surprised when giant robots appear from nowhere to attack New York City. The film takes place in a world where the Great Depression and World War II seemingly never happened, and the only evil one has to fear is the occasional mad scientist.

The mad scientist in question is the mysterious Dr. Totenkopf, played, thanks to the miracles of modern technology, by Sir Laurence Olivier, who died in 1989. The film's other actors are real, but like Olivier, its sets exist only in a computer.

For reasons I won't spoil, Totenkopf dispatches his henchwoman (Bai Ling) with an army of giant robots and bat-like airplanes to kidnap several German scientists and steal various bits of technology and raw materials. As his machines ravage New York, the call goes out to the one man who can save the day.

That man is Joe "Sky Captain" Sullivan (Jude Law), a hero for hire, whose arsenal includes a tricked-out fighter plane and a private army, headquartered on a not-so-secret island base just off New York's coast.

Also on Totenkopf's trail is Sullivan's former lover, ace newspaper reporter Lois Lane. Oops. I mean Polly Perkins, played by Gwyneth Paltrow, who reads her lines with all the enthusiasm of Droopy Dog.

Joe has the firepower to stop Totenkopf, but Polly has the clues leading to the mysterious menace. So, the two are forced into an uneasy partnership, which takes them around the globe in search of Totenkopf's base.

While Joe and Polly's bickering is meant to remind us of screen duos like Spencer Tracy and Katherine Hepburn or Cary Grant and Rosalind Russell, Conran's amateurish dialogue never threatens the standard set by Howard Hawks' "His Girl Friday," and Law and Paltrow never generate romantic sparks. There is better chemistry between Sky Captain and his chief engineer, Dex (Giovanni Ribisi). Make of that what you will.

Conran models his opening, sometimes shot-for-shot, after Max and Dave Fleischer's 1941 Superman cartoon, "The Mechanical Monsters," which, not coincidentally, features robots just like the ones in "Sky Captain." Totenkopf's airplanes flap their wings, an idea swiped from the 1940s comic book "Airboy." And a Tibetan mining facility looks suspiciously like the Trylon and Perisphere built for the 1939 World's Fair. Once you get past the nostalgia, however, there isn't much else.

"Sky Captain" begins well, and the aerial combat amid New York's skyscrapers, with Polly acting as Joe's backseat driver, is the film's high point. Unfortunately, as soon as the action shifts from New York, it becomes obvious that there isn't enough story to sustain a feature-length movie, and the threadbare plot is filled with puzzling lapses of logic. Why do characters refer to World War I as World War I instead of as the Great War when, for all appearances, there hasn't been a World War II? How is it that Totenkopf can build a robot army but must steal power generators?

Angelina Jolie gets third billing, but she doesn't appear until the film's final act, playing a British aviation officer and another of Joe's former love interests. She struts around like a female Nick Fury, complete with eye patch and flying aircraft carrier, neither of which compensates for her atrocious English accent.

Watchful viewers will guess Totenkopf's big secret from the outset. It's no accident that his name first arises during a clandestine meeting between Polly and one of the German scientists at a theater showing "The Wizard of Oz."

The Oz reference is telling. Like the Wizard, "Sky Captain" is all smoke and mirrors.

Pay no attention to the man behind the curtain.