Carlos Casas’s Cemetery arrives on the arthouse streaming service Mubi, a slow sensory film with a magnetic pull of strangeness; it may test the endurance of even Mubi’s hardcore highbrow audience. Somewhere between an experimental art piece and a nature documentary, there’s no story here in the normal sense, and it’s almost entirely wordless. Which is not to say that Cemetery is silent; wildlife audio recordist Chris Watson has put together a wondrously rich sonic landscape of nature sounds.

The setting is Sri Lanka, where an elderly elephant called Nga makes his way to the mythical elephant graveyard. In the first chapter Nga and his human keeper – a mahout – live alongside each other deep in a forest. Casas has said that Nga is a well-known elephant in Sri Lanka, as famous as George Clooney; though surely he’s more of a Bogart – lugubrious and leather-faced.

The camera lingers for 30 or 40 seconds at a time in closeups of different parts of Nga. It gets right up to one of his orangey-brown eyes, almost comically tiny on such a huge head. You find yourself searching for meaning, and Casas is perhaps saying something here about our need to anthropomorphise the natural world. Elsewhere, he creates the point-of-view of the elephant, lumbering through the trees.

In chapter two, poachers arrive, violating the scene with guns and charging the atmosphere with danger. Chapter three feels almost like a parody, as Nga approaches the graveyard in the dead of night: for over 15 minutes the screen is almost entirely black, though the soundtrack is alive with insect chirps. You could just as easily picture this film playing on the white walls of a gallery as a cinema – if either were open.

• Cemetery is available on Mubi from 18 November.