Pig Iron's Fringe show comes with a $400,000 price tag and a cast of 87

Long known for its far-reaching scope, Pig Iron Theatre is taking an epic step toward exploring one of the most fundamental fears of modern society: mass extinction.

The company's collaborators have examined them all — from dinosaurs to trilobites — in A Period of Animate Existence, which descends Friday through Sunday  upon the Annenberg Center with five "movements," a cast of 87, and a $400,000-plus budget — much of it provided by grants from the Pew Center for Arts and Heritage, among others. It eclipses anything in the company's 22-year history.

It's the grandest item in the Philadelphia Fringe Festival — and warranted by the subject.

"All over the world, people are in truly disastrous situations. But to conceive of extinction of our species? Of life on earth? What's the emotion associated with that?" Pig Iron co-artistic director Dan Rothenberg asks. "We are not suggesting policy solution, but giving language to the apprehension. … We're not evolved enough to comprehend it as an emergency. It blows the circuits of our brains."

No surprise that one of his collaborators, Crossing choir director Donald Nally, describes it as "a great big monster of a show."

"It's bigger than we imagined," said Rothenberg. "It's been a lot of years. And a lot of exciting stuff ended up on the cutting-room floor."

What survived, among other things, is a lonely lunchtime food truck whose lighted sign flashes messages — random, poetic, surreal — to customers who have long since disappeared. Or maybe they've transcended their own bodies, loading their genetic information into some futurist computer file. "We jumped to a time that's potentially post-human," said set designer Mimi Lien, "the truck being a pedestrian object on the street that's an artifact of life as we know it today."

Yet little else is simple, especially with collaborators that include the Crossing, the Philadelphia Boys Choir, and the Philadelphia Girls Choir, plus the instrumental group Contemporaneous. More than most Pig Iron shows, Animate Existence is music-driven, though much of that element was "devised," a type of composition born from group improvisation.

"I sat in a room with 15 musicians, described what I was after, and improvised some textures to the point where we got to where we wanted and notated it," said composer Troy Herion, one of the three key creative figures on the piece. "I went back and worked on rhythms and melodies that shoot out." That music — the first that audiences will hear — can seem disarmingly diffuse, an atonal cauldron, not unlike what the Beatles devised in their "A Day in the Life."

Another section approaches the subject with more traditional narrative, as angry children want to know why their future may be disappearing. The final movement unites electronic effects with the  Crossing choir dressed in elaborate red costumes that look vaguely art deco but that actually are more akin to long-extinct sea creatures. The sound of that section, though, is equally open to interpretation.

"Troy took some of the recordings of our workshops and turned them into an electronic file, so you're uncertain if it's us or 'us manipulated,' " said Nally. "We found the key to success is to push against the electronic sound, to try to compete with it at times, until it goes away."

The production has been in a particularly dramatic state of evolution over the last week. Though rehearsed at Swarthmore College's sizable Pearson Hall, the stage was still too small for some of Lien's major set pieces. The sumo wrestlers who go at each other throughout much of the final movement were pared back a bit.

Some of the child cast members in the four movements were completely new to the stage, causing Rothenberg to fend off playful accusations of being a secret sentimentalist for having them so prominently featured in the show. "I identify as an antisentimentalist," he said. "But it seemed perverse to contemplate extinction and leave no room for sentiment."

The use of children brings a levity to the situation of mass extinction. Planetary history is often divided into five extinctions, the climate change that killed dinosaurs being only one of them. Huge volcanic eruptions 251 million years ago destroyed 96 percent of all species. Many experts believe we're in the thick of an extinction right now. "But the other side of extinction is resilience," said Herion. "Those two sides of the coin go together with the history of life on earth."

Spreading the news via the show also briongs certain offbeat pleasures, such as the Crossing's sea-creature costumes. "I'm conducting 12 giant red trilobites while a group of determined young men wrestle in front of them," said Nally. "It beats the hell out of conducting Mozart's Requiem in tuxedos and gowns in a church."