Smaller stories unfold as Suzy Freeman-Greene becomes a face in the crowd.

WE'RE IN A MUDDY field at the docks at dusk. Men in hard hats; kids with footies; women rugged up in parkas and beanies. On our left, Coode Island's white tanks loom. On our right, at the DP World container terminal, mobile cranes dart around like robots. And everywhere, there are containers stacked like matchboxes. Blue, green, red, orange, grey.

We're here to be in a picture - one of artist Simon Terrill's "Crowd Theory" photographs. Most of us have some sort of connection to the place, whether as a truckie, a port worker or a neighbour and many elaborated on this link when signing up for the shoot. Somewhere in our group I know there's a former milkman to the wharves; a man who spent 17 years fixing ships' phones; an ex-punk musician who once had a song called Docks of Melbourne and a romantic who simply declared: "I dig ships".

Terrill has been photographing crowds for four years: both "constructed" ones such as this and actual audiences at rock concerts. He talks of the liberating anonymity of the crowd and the fleeting relationships that can develop there.

Tonight about 180 people will be photographed amid the docks' "mesmerising, sci-fi landscape". Terrill is interested in our individual gestures and the spontaneous groupings we may form. As gold-flecked clouds gather above and a truck rumbles by, he tells us: "What we are hoping to do tonight is quite simply make an unforgettable image. We will take just 10 photographs ... I want to invite you into this picture."

The camera is on a 6.5-metre-high platform. The exposures will be 15 seconds long. We can do anything during the shoot, except look at the lens. And Terrill wants us to hold one thought. "What does this piece of strange land mean to you?" he asks. "This piece of reclaimed swamp. Just think port thoughts."

He heads off to the platform and we wander into the area marked out for the shoot. One woman has her hair lacquered above her head, mohawk-style. Another is wearing a parka with the words "Stop Toxic Spew" painted across the front.

I chat to some men in rain jackets. Larry Wooding, a waterways ranger who used to be a merchant seaman, tells me: "This is quite a personal experience. I'm going to reflect on the time I spent at sea."

Peter Somerville owns the Blackbird, an old-fashioned ferry that cruises the Maribyrnong and the port. An exuberant man with eyes twinkling under a peaked cap, he tells me: "I've spent 28 years on the waterways. I love it." In 1991, he sat on the Blackbird watching the tanks of Coode Island explode. "Oooh, it was interesting ... the volume of smoke and the flames going up."

As we talk, a massive ship sails out, stacked high with boxes. Then a blast of music alerts us to our first photo. I stare blankly, like a rabbit in headlights, then focus on a man in a hard hat holding up a flag with the help of a woman wearing a blazer, leggings and what seems to be a feather boa. It turns out he's Ken Cahill, chaplain of the Mission to Seafarers, here with some mission volunteers.

Shot Two. A couple hug. A man points at some imaginary place in the distance. I turn to the container stacks and meditate on them. I used to live near the docks and trucks would trundle up my street, spewing diesel fumes and crunching air brakes. I hated them but how empty would my life be without the contents of their boxes?

It's getting darker. Music blares from speakers and people seem to be loosening up. A man in a blazer is playing the trombone. He tells me he's in the Footscray-Yarraville City Band. Another shot. He points his trombone towards the heavens.

White lights shimmer amid cranes and gantries. It's freezing but it feels like a privilege to be here. About 3200 ships come to the docks each year. Security is strict and the place is usually off limits. The last time I was here was to report on the wharfies' dispute in 1998, when the air was thick with passion.

Fifteen film lights have been turned on at our site. Children cast long shadows across the mud. I chat to some port staff. Evda Marangos, who manages cruise ships at Station Pier, tells me she has been thinking about the day, 40 years ago, when she met her grandmother there on a ship from Greece.

Behind us, there's an open shipping container housing a light, and for shot six I step inside. It's thick-walled; the size of a small bedroom. I think of stowaways, people desperate to escape.

Shot seven. Kids crouch in the grass. A man stands perfectly still with his eyes closed. A couple kiss. A chap from the Beacon Cove neighbourhood association tells me he has been thinking about globalisation and productivity during the shoots.

Bright, white seagulls gleam against the sky. I face the docks again and watch the cranes moving steadfastly, lifting, shifting boxes. The containers seem so anonymous yet they're filled with stuff we value: cars, food, clothes, toys, bikes.

Shot eight. A girl does a handstand in the mud, her legs held up by two friends. It ends and she falls into a dirty puddle.

A man tells me he has been thinking about the port as a route for illegal drugs to enter the country. He works as a drug and alcohol educator.

A lean guy in a hoodie tells me he's an instructor in parkour, a form of physical activity that's about overcoming obstacles as efficiently as possible. He has been looking longingly at the containers, wishing he could get over the wire fence and have some fun. What would he do in there? "I'd shimmy up those pylons, climb across the top of the gantry and jump across containers."

Our last shot. My "port thoughts" have become a jumble of sensations. It's cold, the sky's black, there are sirens beeping behind me but I'm enjoying this place, the strange democracy of this experience. It feels like we've been through something together - something ineffable and faintly mysterious - and I'm not ready to return to the real world.

My last conversation is with Jimmy Jack, a bearded, semi-trailer driver. He says working on the wharf at night is "grouse". But he has really enjoyed mingling with different people on the other side of the fence. "Normally my mind is in overdrive but it was so relaxing," he says of the shoot. "It felt really good." As I leave, he and the trombone player are discussing the latest size container trucks.

A few days later I call Terrill and ask him how it went. "I think it went well," he says, sounding slightly doubtful.

This is his fifth "Crowd Theory" photograph, a collaboration with the Footscray Community Arts Centre. The others were taken at the centre, in a Braybrook park, at Footscray train station and at Southbank. Terrill is influenced by the richly detailed work of the 16th-century Flemish painter Pieter Bruegel. His photos do not have Bruegel's overarching moral narratives. But he likes the idea of the grand, historical picture filled with smaller stories.

His final image will measure 1.8metres by 2.4 metres. He thinks it will be one of the later shots, from number seven onwards. Earlier, people seemed to be performing but by the end they'd entered "a more private, more interesting place". And the space was filled up beautifully. "I guess people had claimed it as theirs by then."

Crowd Theory Port of Melbourne will be at the Mission to Seafarers from August 29 to September 21.