Tim Robbins slings one enormously long leg over the other, tilts his head to one side, and considers his last sentence as if the words hang in the air in front of him. "It's king of an ... eccentric ... industrial ... comedy," he says of Ethan and Joel Coen's The Hudsucker Proxy, which began shooting in North Carolina in December. "Yeah," he continues, liking the sound of it, "a comedy of industry."

Right. So what's it about?

In the Warner Bros. movie, due late this year, Robbins plays a rube in the big city who in one day goes from being mail clerk to president of Hudsucker Industries. Paul Newman is a back-stabbing coworker, and Jennifer Jason Leigh plays a reporter/love interest.

And Hudsucker manufactures what? "Ah, that's the biggest secret of all," Robbins says archly.

The brothers Coen - Ethan produces, Joel directs -- who speak as if locked in a Vulcan mind meld, aren't willing to give up much more.

Joel: Well -

Ethan: That's -

Joel: Nobody knows.

Ethan: They're in business. With a budget estimated at $30 million, Hudsucker is the Coens' most expensive movie yet. And after a string of offbeat films - Blood Simple, Raising Arizona, Miller's Crossing, and Barton Fink - the brothers look on Hudsucker as their plunge into the mainstream.

Joel: Nobody will be scratching their heads in this one wondering, "what the hell..." It's a comedy.

Ethan: A family picture.

So the Coens have constructed a cartoonish uber-urban rendering of 1950s New York. "The movie," says Joel, "takes place 95 percent in this one skyscraper in New York. The scenes that aren't in the building are actually when people go out windows." Go out windows?

Ethan: Falling sequence -

Joel: -- for various reasons. The overscale set has a lot to do with the overscale budget -- and, apparently with the overscale leading man. "This was a good marriage between the part and the actor," Joel says. "He's tall."

For Robbins - last seen as a politico-songster in Bob Roberts and The Player's soulless Griffin Mill - Hudsucker offered a chance to play a nice guy. "It's been a real relief," Robbing says, "not to have to greet the Prince of Darkness every day."

Maybe, but the Prince of Darkness has served Robbins well and may earn him an Oscar nod when nominations are announced next week. Still, he is hardly complacent. "I want to work with people like the Coens who challenge my perceptions. I'm having a wonderful time on Hudsucker," he says and allows a little angst to slip out. "I don't want to get too comfortable with whatever ephemeral success there is. It makes me more nervous."