Moviegoers watching "Coming at Ya!" a new 3-D film replete with special effects, at the Arlington NTI Theater yesterday thought that the smoke filling the theater during an exciting flame-throwing scene was just another wild special effect.

It wasn't.

In fact, the 143 people in the audience burst into laughter when theater manager Pat Rosensteel brought up the house lights and asked them to clear the building.

"I had to tell them fire trucks were coming before they realized I wasn't kidding," Rosensteel said.

A spokesman for the Arlington fire department, which sent six trucks to the scene, said smoke started to fill the theater around 2:15 p.m. when a fan in the basement redirected the smoke of "an overheated old motor" through the theater's ventilation system.

There were no injuries and no damage to the theater.

After a 20-minute wait on the sidewalk in front of the theater at 2901 Columbia Pike, members of the audience returned inside, put on their 3-D glasses and rewatched the pivitol scene -- without smoke.

"This picture's got all sorts of effects," said Rosensteel, explaining that the smoke filled the theater just as an Indian was shooting flaming arrows at the hero and a barn was erupting in flames. "I guess people though they were getting as little smell-o-rama for their money."

Jim Morris, an Arlington resident who was watching the movie said afterwards, "I just figured they were blowing the smoke in for the scene and that they would suck it out as soon as it was over."

"I thought, wow, this is pretty good. They never told us there were going to be effects like this," Morris said.

Morris said that the smoke was especially believable as a special affect because "You could really smell it, but it didn't obscure your view of the screen."