Heather Nicol channelled her memories of living in Manhattan on 9/11 into a monumental art project

Contains strong language.

I'd just left Period 1 Phys. Ed. when I first saw it: the towers, the planes. I squeezed into a group huddled beneath the TV screen in my high school's foyer. And for the rest of the day, in every class, we watched the news. Then, when I went home, I watched for hours more.

For most people, 9/11 was an intense, mediated experience. But for Toronto-based artist Heather Nicol, it's not the images she remembers most — it's the sound.

Nicol was living in Lower Manhattan at the time. Her two young children were attending school a couple blocks away from the World Trade Centre. When she heard the crash, then saw where the plane had struck, she left in a hurry with her neighbour to retrieve the kids.

The second plane hit as they started toward the school. Ambulances and fire trucks went screaming past. They'd picked up the children and were seven blocks away when the South Tower fell.

"Suddenly, it was really loud," the artist remembers. "I thought it was an atomic bomb, because it had that weird non-specified sound. There wasn't an explosion where there's a bang — just suddenly, this roaring sound began." People on the street screamed. Someone nearby yelled, "We're all going to die."

"It was fucking awful," she says. But Nicol, her kids, and their neighbour kept walking, through SoHo to Little Italy and home. For months after, her teeth chattered. "It was like my bones were rattling." The noise of the catastrophe had been recorded deeply in her body.

20 years on, the artist reflects on that tragedy with an immersive audio and visual installation titled September Song. It is a monumental work about memory, history, trauma, and resilience.

From the rafters of Toronto's Harbourfront Centre Theatre, a baby grand piano, painted white, hangs precariously on silk ribbons as if frozen mid-fall. The dangling instrument represents fear, threat, and "the idea that everything can change in a flash," Nicol says.

The artwork's score doesn't contain a crash. She does not recreate the roaring noise that rattled her bones. Nor are there screams of terror. "This is not a desire to bring audiences to Lower Manhattan on that morning," she says. September Song is as much about the reverberations of that day as it is about the day itself. "It's taken me this long to really know what that sounds like."

Voices emanate from throughout the space. They do not sing lyrics — Nicol didn't want to privilege any one language. Instead, the chorus forms notes and makes other vocalizations. For example, Nicol asked her performers to imagine they're jumping off a high diving board or to pretend they're at a bar and they've just been shoved. She wanted to explore the sudden shift between certainty and uncertainty, between pleasure and terror, and to record what that "absolute twist of fate" might sound like.

The chorus is accompanied by piano and bowed saw. Nicol worked with pianist Eve Egoyan to develop a series of musical "poems" — little chapters that are distinct but interrelated and which function the way memory does, recurring with a slightly new focus upon each return. The piano's "poems" ebb and flow, imitating the passage of time and the rippling nature of experience. At various moments, the song is grand, sombre, melancholy, curious, even joyous; it encompasses the range of emotions this 20-year saga has produced.

All the while, tiny bits of white paper flutter down from the ceiling, like ash. And a lone figure — the only performer present — dutifully sweeps the confetti into a pile and then drags it from the room. For Nicol, the sweeper represents the first responders, the frontline workers, the caregivers.

"It really is about resilience and the dignity of that labour, you know — we rebuild, we clean it up, we keep at it." During an early performance, one viewer was so overwhelmed by the immensity of the sweeper's task that he was compelled to take the broom and help her.

The work, it seems, is never-ending. The ripples extend forever and they go in all directions. The terrible event 20 years ago that spawned more terrible events was itself precipitated by terrible events before it. September Song brims with both damnation and hope, when it suggests we will forever be sweeping up from our history.

Heather Nicol's September Song runs through Sept.19 at the Harbourfront Centre Theatre. Admission is free. Register for your timed entry here.