People in the entertainment industry sometimes speak about performers having the “it” factor – a difficult to define quality not necessarily apparent in real life, but ushered into shimmering existence on stage or screen.

Nobody in the world has ever had “it” quite like the great Yolŋu actor David Gulpilil, a titanic force in Australian cinema and now the subject of director Molly Reynolds’ superb, sad, yet in its own way wonder-filled documentary, which achieves the intimidating task of doing justice to the life and career of this extraordinary artist.

Reynolds understands that Gulpilil isn’t just a great actor but a portal to a different way of thinking, a different way of being, even a different state of consciousness. If you think that sounds like hyperbole, you have not seen a David Gulpilil movie.

Plenty are sampled in My Name Is Gulpilil, which oscillates between present and past, drawing on portrayals plucked from the actor’s rich oeuvre to illustrate different parts of his life and character – his story, this time, not someone else’s. Moments from his films (so smoothly integrated by editor Tania M. Nehme) feature like personal footprints, snapshots of a life impressed on to celluloid.

The film plays out in the spirit of a living wake, celebrating its subject while contemplating the inevitable. One Buñuelian shot captures the actor from above, lying with his eyes closed in a coffin with red lining, his body covered in old film reels. They flow out of it, as if they are a natural part of the man himself.

In a sense, of course, they are. Gulpilil has been present on our screens for a full half century, his career beginning with a breakthrough performance in Nicolas Roeg’s great 1971 film Walkabout. Back then Gulpilil was a teenager with a cheeky gleam in his eyes – now, in his 60s with lung cancer, his spirit and humour are still apparent but those eyes have dimmed.

Living in Murray Bridge, South Australia with his carer Mary, who he says will be “with me until I’m gone”, we see Gulpilil take pills – including for pain management and anxiety – and puff on an inhaler. Throughout the course of the running time he philosophises on differences in attitudes towards medicine in white and Indigenous cultures, the former involving its determination to “win” – to “beat” or “conquer” illness. But Gulpilil is under no illusions about his own situation, declaring he is going “back to country on a one-way ticket”.

He introduces the film as “my story of my story”, implying dual layers: his life and his life in film. There have been other nonfiction productions about or involving the actor, including Bill Leimbach’s 48-minute documentary Walkabout to Hollywood, from 1980, which contains interesting footage revealing Gulpilil’s intellect and personality as a (much younger) artist. And another directed by Reynolds – 2015’s excellent Another Country, an essay-like analysis of Gulpilil’s then home town of Ramingining in the Northern Territory, which uses the location as a case study to explore incompatible aspects of white and Indigenous Australian cultures.

But My Name Is Gulpilil is on another level: so sublimely made, so humane, so elegant in construction. Among other things, it is a reflection on mortality and an acknowledgment of the movie medium as a form of mausoleum, fossilising (though the great director Andrei Tarkovsky preferred to call this “sculpting”) moments in time, and here, bringing them back, for a story of a story.

Several moments show Gulpilil walking towards the camera, or walking away. Sometimes he does this in the same shot. Always these moments crystallise a subtextual message about looking forward and looking backwards. The director does so without turning a blind eye to her subject’s shortcomings; in one scene Gulpilil stands alone in a hospital or medical centre corridor, as we hear audio snippets from news bulletins reporting on controversies and criminal charges he faced over years – like grim memories tumbling around his psyche.

Seeing present-day Gulpilil on a boat evokes memories of films that position him close to water, geographically and spiritually. Among them, the creature feature Dark Age, about the pursuit of a “dreaming croc”, Peter Weir’s end-times drama The Last Wave, the final moments of Goldstone, which present Gulpilil as a kind of whispered memory in the mind of Aaron Pedersen, and those sublime coastal scenes from the original Storm Boy.

Elsewhere in the documentary, in a personal reflection from the man himself, we learn that “Gulpilil” means “Kingfisher”. And so, all those scenes next to water retrospectively acquire an almost cosmic sense of purpose, as if positioning the great actor near creeks, rivers, oceans was preordained. Pensive and piercingly emotional, this is an unforgettable film.