New York ? A smoke-breathing dragon flaps its wings and cranks its head. Monkeys fly from a tangle of vines that frames a giant fantasy clock. A witch in a sparkling blue gown travels on a bubble-blowing pendulum. And a green witch in a black hat flies her broomstick through billows of smoke.

All these special effects happen within the $1.5 million set of “Wicked,” a new musical at the Gershwin Theatre that tells the story of “The Wizard of Oz” from the viewpoint of the witches who made life such a challenge for Dorothy in the classic 1939 film.

“Wicked” puts a new twist on a story that parallels the familiar movie. Kristin Chenoweth, as Glinda the “good” witch, demonstrates a knack for one-liners that keeps the audience laughing, despite the dark debate over goodness and wickedness. However, the precise and brisk staging makes the nearly three-hour show pass quickly.

The movie was based on a series of novels by L. Frank Baum, while “Wicked,” the musical, draws inspiration from the novel of that title by Gregory Maguire.

Designer Eugene Lee, who has won Tony Awards for a revival of Leonard Bernstein’s “Candide” and Stephen Sondheim’s “Sweeney Todd,” gives only passing notice to the famous yellow brick road in his elaborate set.

Lee, 64, his white hair cropped short and his bow tie loosely knotted, smiles often when he talks about this project. “Where else can you build a dragon?” he asks.

He began by reading the Maguire novel, then drew a series of sketches to transfer Maguire’s vision of Oz onto a stage. He assembled a scale model which he presented to director Joe Mantello, book writer Winnie Holzman, composer Stephen Schwartz, the producers, and ultimately, the full company — “a great collaboration,” Lee says.

The work was complicated. “We are both architects and engineers,” says Lee.

“And sometimes, mechanics,” adds associate set designer Edward Pierce, 33, whom Lee credits with assembling the many parts of the project and making them all work.

Complicated staging

One of Pierce’s jobs was to use computer software to convert Lee’s sketches into precise drawings for mechanics, carpenters, electricians and technicians who would build the scenery. The set was made from steel and other basic materials — aluminum, fiberglass, plastic, fabric and natural vines that serve as launching pads for the flying monkeys.

Lee designed the big clock, based on “a kind of mad clock” from the Maguire novel, and defined his vision by creating a series of moving panels of gears and cog wheels that became the central image for the set. Cued to the music and lighting by computers, the panels and the wheels seem in constant motion during transitions from one song and scene to the next, rolling and sliding along the floor in grooves disguised by clouds of smoke. The clock image envelops all the characters in the Oz story.

“Lots of smoke comes through these,” Lee says backstage as he points to tiny slots cut into the false maple floor that serves as the platform for the show’s big dance numbers. The smoke, which maintains the sinister atmosphere of this ornate fantasyland, also obscures several trap doors where characters appear and disappear from time to time.

Since “Wicked” opened, Lee has returned several times to gauge audience reaction to those moments when the set plays a big role.

Elphaba, the “wicked” witch, has a flying scene that ends Act 1. Lee calls it an important storytelling moment and an audience favorite. Director Mantello wanted Elphaba, played by Idina Menzel, to show her mastery of the broomstick that rises magically through a trap door. She grabs the broom, mounts it and takes flight singing the number “Defying Gravity.”

To achieve the effect, Lee and Pierce designed a telescoping arm that the audience never sees because it is hidden by the ubiquitous smoke and many yards of dark fabric.

“She still needs the freedom to sing, so we didn’t want to use a harness,” said Pierce.

‘Respect the set’

The task of coordinating all this action with the show’s music, lighting and scenery while transitions flow perfectly, night after night, fell to production supervisor Steven Beckler. The stage manager sequences cues to the music, giving signals to computer console operators who in turn automate the movement of scenery with the lighting.

Of course, Beckler prefers that the audience hardly notices the transitions, when gear panels slide out and beds seem to slide into place just in time for witches to flop onto them.

Still, no matter how perfect the automation, it poses some hazards.

While Chenoweth considers Lee’s scenery “just genius,” she acknowledges the tricky set has given her “a couple of hard moments” in her role of Glinda.

On one occasion, an automated light tower struck Chenoweth, knocking her out for a few moments. “I woke up in time for the next scene, but had a knot on my head.”

The incident taught her a lesson: “You have to respect the set. There’s no stopping those panels and towers.”

The gowns that Chenoweth wears in most scenes also have forced her to pay close attention as she scampers through narrow passages and stairways. “You have to be aware all the time of your spacing,” she says. “I wear a huge dress, and sometimes it gets caught on those vines.”

While the computer cues are all choreography down to the beat of a musical note, some of the staging remains in the hands of humans, especially the flying elements, like the monkeys. A backstage crew controls the cables that allow them to soar.

“We had to learn a flying pattern,” says LJ Jellison, who plays one of two monkeys who fly over the audience in Act 2. “And we have to avoid mid-air collisions.” So far, the monkey actors have only sustained a few bumps during rehearsals.

“Wicked” received mixed reviews when it opened just before Halloween, but word-of-mouth assured nearly full houses beyond the holiday season. As Chenoweth says, “It feels good to have a hit on your hands.”