This studio is found in The Parlor - as in former funeral parlor, where the interior is being renovated slowly into places for artists to work. This is Broad Street way south of all the spiffy Avenue of the Arts stuff (though Pennsylvania Ballet is across the street). No matter what anyone claims, this part of Philly does not look like Paris.

Headlong polished their gleaming studio floor themselves, and happily take you into an adjoining room where the floor has yet to be refinished so you can appreciate how worn, darkened and pocked with holes the surface was before they go to work. "That's us," laughs David Brick, "floor refinishing and postmodern dance. Step right up."

This day the Headlong threesome (Brick, Andrew Simonet and Amy Smith, joint artistic directors, constant collaborators) is polishing up a premiere called Story of a Panic for their Painted Bride run this weekend. NEA funded the project, which includes musical collaboration with local composer Rick Henderson.

The name and inspiration comes from an E.M. Forster story with a dark and pockmarked subject - also not very Degas. But they've brought this odd subject to gleaming life, like the floor - just as they've done with other odd subjects such as the movie Star Wars (their riff on this won them a Bessie, the NY Dance and Performance Award) and James Joyce's Ulysses, a recent exploration.

Simonet found the Forster story and couldn't get it out of his mind. He was fascinated by the story's staid British narrative tone interrupted by an incident provoking panic in the characters - "blank expressionless fear," Simonet observes.

Then the story resumes using exactly the same "incredibly stuffy" voice and pace. "The sense that our world can rupture open like that is so inspirational to me," Simonet says.

So Story of a Panic started not as a way of moving, but as an idea. "We are the total nerds of the dance world," Smith laughs. "There aren't many others pursuing concepts and ideas as the basis of what they do." They presented a preliminary sketch of Panic a couple of years ago, but the piece this weekend bears almost no relationship to that earlier work. "In the intervening time," Simonet stresses, "we developed better strategies to do a piece like this."

The main strategy was to create a kind of "panic" boot camp at their studio. Under the guidance of Simonet, the primary creator of this piece, the dancers were run through a series of exercises to see what panic looked like from the outside and to experience how it felt from the inside, and then to begin to shape that material into movement. This involved all three Headlong collaborators, Brick, Smith and Simonet, plus their company of Christy Lee, Nichole Canuso and Heather Murphy. They went through a kind of Parris Island experience looking at tapes of disasters, car wrecks, earthquakes. They wandered around blindfolded. They wrote about how their bodies reacted in panic. They analyzed what those movements looked like. And they examined how they felt in this process.

"We do 'psychic choreography'," Smith emphasizes. "In each moment we know who we are in what we're doing. Not in the sense of the theater where the performer is very specific. It's more like Impossible Dance [also on the Bride program] in which there is a section where we try to imagine floating. So our faces have to reflect that…it's not like playing a particular person, but not just choreographing a step either, but truly imaging what it feels like to float."

For the visitor, crouched against the studio wall watching a run-through of Panic, the dancers' movements just inches away echo internally. As bodies contract, jerk, coil, the fear is palpable even on this benign day. The pulse accelerates.

Headlong, for all of its deserved reputation for improvisation, humor and spontaneity, make highly structured and polished performance pieces. They use all the tools available to them as postmodern dance creators. People have to get to the right place on stage at the right time and to do this the company uses dance's traditional method of counting. "You need 16 counts of three to get across that space," they might be told.

But Headlong doesn't just count out a piece. There are points in the composition where actual movements can be improvised by the individual in the best experimental tradition. And the dancers occasionally pace their moves by watching one person. "Watch Heather's foot here," they're told. And they all do just that, turning their own feet in waving patterns that follow Murphy's. And sometime s they're cued by the music itself, knowing that at a certain place in the score they must do this or be exactly there.

This is the engineering, the algebra, of dance: making movement into a text or formula that can be repeated like a play or concerto. Without strict adherence to a way of setting the dance, dangerous things happen. In rehearsal Murphy got a knee in her temple when the pace was off. Everything stopped. The dancers sat protectively in a circle around Murphy while she held an ice pack to her head. Then they quietly walked through the move where Murphy was hurt to see who was where, and who was off count or what. They went over and over the section. Faster and faster. Finally repeating it pretty much full out. Everyone confident, even Murphy.

But at the end of the run-through the piece was 17 seconds off. Between now and the premiere's opening performance those 17 seconds will be found and corrected. As Simonet stresses, "The piece is intentionally made to look very immediate, but it is tightly set and choreographed. The dancers have been incredibly brave and courageous, mentally and physically."

The Bride program includes Impossible Dance with no music; the Headlongers just talk. And also Your Heart Turned Left, I Was On the Right, a country-western piece originally performed in a club setting and still full of that easy-going spirit. It's also funny; actually, everything Headlong does is funny in some way, even Panic.