Just three months shy of its spring opening, Revenge of the Mummy is part construction site, part thrill ride.

Its maze of stage sets is nearly complete, and a roller-coaster track coils like a whip through its building on the back lot at Universal Studios Florida.

But a foam cutout holds the place of a robotic figure in one scene, and no one passing by seems surprised by the demon warriors springing from their hiding spaces as workers check whether the monsters are operating properly.

Universal has a reputation for edgy attractions, but executives say Mummy, which is entering its final weeks of construction, will be unlike anything the company has built.

It will take passengers on a four-minute "psychological thrill ride" that includes a skeletal villain, a roomful of flesh-eating bugs and a chamber where real flames roil overhead.

A ride as elaborate as this one is "a very complicated thing to pull together," said Scott Trowbridge, vice president of Universal Creative, which designs attractions for Vivendi Universal's five parks in the United States, Spain and Japan.

It also is crucial to keeping Universal competitive with its archrival Walt Disney World, theme-park consultant Dennis Speigel said.

Competition between the resorts "continues to be an armaments war, and if you don't come out with a big gun," you're not going to attract tourists, said Speigel, president of International Theme Park Services, a Cincinnati consulting firm.

Construction on the Mummy started more than a year ago, even before Universal unwrapped plans to spend $80 million on a pair of Mummy attractions at its theme parks in California and Orlando.

In fact, an army of artists and engineers had been working on the attractions since before the movie that inspired them was released in spring 1999.

That's not unusual.

Ride designers typically start thinking about possible rides several years out because it takes so long to build them, Trowbridge said.

Some of those ride plans are shelved because the story is weak, while others are filed away because they would cost too much to build or there's no room for them, he said.

But building a thrill ride based on The Mummy was "a natural," Trowbridge said.

The movie, like its 2001 sequel, The Mummy Returns, is about a mummy, Imhotep, who returns from the dead and wreaks havoc.

"We thought, 'Here's a story line that's classic Universal,' " Trowbridge said.

Company officials are careful about what they will say about the ride. Universal will talk about the making of the attraction but won't say what happens after the first few scenes, and it won't allow photos of the work in progress.

One of the first decisions the designers made was to have the attraction combine an indoor attraction with a roller coaster -- an idea that had been on the shelf since the early 1990s.

Space Mountain and Rock Rock 'n' Roller Coaster at Disney are indoor coasters, but Mummy will be different because the coaster is simply one more twist in the attraction's plot.