At first glance, Gareth Sansom’s paintings thrash about on the canvas, seemingly doing battle with themselves. Keep looking. The canvases – some more than five metres wide – refuse to settle into something flat and easily digestible. They’re enduring visual assaults. They have the make-up of collage, and the feel of self-contained worlds.

In the 1960s, artists such as Arthur Boyd and Sidney Nolan represented the dignified voice of contemporary Australian art, with their rich landscapes, modernist portraits and mythologising of colonial history. At the same time, Sansom was pushing paint into riotous configurations, incorporating collage, crayon and photographs, and referencing film, religion, war and cricket. He was way ahead of his time. Fifty years later, and now regarded as one of Australia’s most acclaimed and important artists, he hasn’t stopped.

“By the end of art school he already had an idea of what he was reacting against,” says Simon Maidment, who curated the new Sansom retrospective, Transformer, at the National Gallery of Victoria.

“He’s not religious, but he grew up in a devout Catholic family,” Maidment continues. “His father had lost an arm during the war. I think the trauma he saw as a young boy infects his whole career. There’s a streak of mortality through everything.”

On top of that, Sansom regularly refers to cinema, be it Ingmar Bergman’s The Seventh Seal, Stanley Kubrick’s The Shining or Alfred Hitchcock’s Psycho. “He has a fascination with the men in those films,” Maidment explains. “He’s drawn to characters that exist on the periphery, performing a role.”

Later in his career, Sansom took to photography and digital collage, exploring sexual imagery, scarred bodies and pierced penises, all in confronting close-up, blurring the border between pleasure and pain. He took self-portraits in which he performed non-heteronormative roles.

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There’s a strong continuity from his earliest paintings right up to the titular 2017 work Transformer. Maidment wasn’t familiar with Sansom’s whole career when he set out to curate this show, and was surprised to see the consistency across the decades. That’s why he’s placed paintings from the ’60s alongside contemporary works, which are a little less wild-eyed but no less irreverent.

Crossovers appear between works that were created decades apart, many of which have never been in the same room before.

“There are a couple of times that we’ve hung paintings next to each other that have incredibly similar compositional structures,” says Maidment. “It’s amazing. Those chaotic landscapes continue off the edge of the painting and into infinity.”

Gareth Sansom: Transformer is at NGV Australia until January 28.

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