The headquarters of Circus Oz is a large converted-warehouse-style building tucked down a Collingwood side street. When I open the door a bell rings, and I walk up the steps to see a handful of performers hard at work on rehearsals for a new show.

It's hard to know where to focus my attention. Do I look at the grown man on the floor dressed as a baby, surrounded by toys including a miniature drum kit and a glockenspiel? Or the man with the handlebar moustache and tights (emphasis on the tight) playing the bass guitar? Or up at the web of bars and ropes, one-and-a-half storeys up, from which performers will soon be suspended?

“Circus involves real risk,” says artistic director Rob Tannion. “There are lives in hands. And egos in hands.”

Circus Oz has been pulling off this balancing trick for nearly 40 years, and there’s reminders throughout the building. Framed on one wall is the peak of Circus Oz's original tent, sewn and welded by the founding crew in 1978, now frayed and discoloured. In another room, the “Breville of Death” contraption, a twist on the classic bed-of-nails stunt, but with twice the nails. For dangerous work, it all looks suspiciously like play.

A new direction

Tannion is new to the Circus Oz family; he’s been at the helm now for just over a year. He’s on the cusp of seeing his first show as artistic director, Model Citizens, launch in Melbourne on June 20 under the “heated big top” at Birrarung Marr. Like many of Circus Oz’s shows, Model Citizens is a high-concept show that marries the political with the personal, while being as playful as ever.

The show introduces us to a model-kit world of oversized props and odd scaling affects, drawing us into Circus Oz’s unique world-view. “If the world is a model kit,” says Tannion, “what of the pieces that don’t fit?”

“What does it mean to be a model citizen?” he asks. “We want individualism, but we don’t want people to stray too far from the box. The idea of the ideal citizen is getting harder [to quantify].”

This theme has personal resonance for Tannion. Last year he returned to Australia after 20 years abroad, most of which was spent in Spain. “I always very much identified with my Australian heritage [while away],” he says. “I tried to hang onto it wherever I was, I was always a foreigner.”

To tie these personal themes to the familiar, Tannion wanted to take everyday objects and turn them into circus apparatus. “If I asked my mum, who’s got nothing to do with circus, to come to a show,” he says, “she’d say, what does a cyr wheel or trapeze have to do with her life? Nothing. But if someone’s climbing a stack of giant credit cards, or the Chinese pole becomes a giant safety pin, that comes with built-in function and meaning.”

It’s not all political and metaphorical. For Model Citizens, Tannion wanted to devise an aerial act involving a giant pair of underpants simply because he thought it would be funny. But not everything made the cut. The giant gum dispenser spitting out bowling balls proved a touch too impractical.

Props and pegs in the workshop

Downstairs the prop store is one of the more chaotic rooms in the building. High racks and shelves heave with objects of all shapes and sizes, tools and materials are spread around and a blackboard on the wall is covered with inscrutable scrawls, alongside pinned-up drawings, photographs and colour swatches. This is where set and prop designer Michael Baxter works.

Today, among the colours and notebooks on his desk, is a huge spool of rope. Baxter says the rope is made from Dyneema, a high-performance polyethylene that’s stronger than steel, but light enough to float in water.

“The overhead bridge in this show is the most complicated bit of splicing (interweaving strands of a rope so it joins without the use of knots) I’ve ever done,” says Baxter. Before he ran off to join the circus, Baxter was a yacht rigger and, at various points, a crayon manufacturer and skateboard builder. At Circus Oz he gets to use all these skills in a job as much about safety and problem solving as it is ingenuity and wild ideas.

“I was never interested in performance before getting into circus,” says Baxter. “I don’t think I even saw any theatre until I was 19.” In his twenties he was asked to help with some rigging for a small circus troupe, and it’s been a part of his life ever since.

Baxter sits down and draws me a picture of what he’s currently building for Model Citizens. It’s, a vast, oversized model-kit frame containing body parts and objects ready to snap out. A giant peg operates as an acrobatic springboard. When finished it will be 20 metres wide. “Our lives are a model kit,” he tells me. “We build our lives from what we find, put ourselves together.”

The set is designed to disorientate, he says. Scale is blown out of proportion, and it’s painted in International Klein Blue, a colour so rich it’s hard for the eye to focus on. “It seems to bend light waves around it,” says Baxter.

In a corner there’s the aforementioned oversized credit cards, each a metre-long. Baxter stacks them like a house of cards, six cards high. Someone’s going to climb on top of that, he tells me, and they’re going to fall off. It’s based on a Chinese balancing chair act, which is a common circus routine, only now it’s about balance transfers, the whole thing collapsing under the financial strain.

Dressing for the occasion

As a founding member of Circus Oz, costume designer and head of wardrobe Laurel Frank has been witness to every change in the company’s 39-year history. Including the people that come to see it.

“It was the politics of the company that first interested me,” says Frank. “Then I got dragged into the whole circus world. But it’s very different now. Audiences are more sophisticated. There’s still a very strong motivation to talk about political things, but it has to be funny and sophisticated and subtle.”

Frank’s workshop is a big jam-packed room on the third level of the building. It’s crammed with sewing machines, mannequins, high shelves holding fabric, and giant spools of cotton thread spilling across the walkways. Technically this room is Frank’s alone, though when a show is in development she employs casually a team of assistants, including a cutter, milliner and a small group of machinists.

Costume design for the circus presents specific challenges ordinary theatre doesn’t says Frank. “With theatre it’s about character and text and words,” she says. “But circus is a physical language. It’s closer to dance. So it’s about finding physical expressions that reflect their character.”

There’s also safety considerations in costume-making. How long can each kangaroo-costume tail be before it interferes with a somersault? How do you design a hat that still looks like a hat after it’s been battered in a circus ring?

Frank pulls out a damaged costume. There’s a hole torn straight through the upper thigh, surrounded by what look like burn marks where the fabric caught on a pole. “Things like this look very basic but they’re very technical as well,” says Frank. “I spend a lot of my time thinking about safety.”

Laurel’s costumes for Model Citizens evoke everything from picket fences to PVC bondage gear. “The show is about ideal types,” she says. “You can’t just present a series of people in suits and uniforms. I need to look at that idea in surprising ways.”

Adjacent to Frank’s workshop is a storeroom heaving with history. It’s where Frank keeps the things she’s made across Circus Oz’s 39 years. “If I add any more racks in here I won’t be able to move the ladder around,” she sighs.

Today Frank is working on a schnauzer costume. “We’ll need to bring the neck in quite a bit, and work out a way to get the long whiskery bits looking right,” she tells me, holding up a photograph of a beaming schnauzer pup. She sees the amusement on my face. “This is my life,” she shrugs.

Circus Oz: Model Citizens runs from June 20 to July 16, under the heated big top at Birrarung Marr. Book tickets here.