The late Icelandic composer Jóhann Jóhannsson adapted British philosopher Olaf Stapledon’s science fiction, Last and First Men, for his 70-minute film. This is the only film Johannsson ever made. As well as directing, he co-wrote the music and co-produced it.

It begins in silence. Gradually a misty landscape unfold. The sound of wind, then two chords are repeated. A slow transition to an uncanny structure is followed by similar images. They have an air of unworldliness but in fact, they were built in former Yugoslavia in the 1950s and ‘60s.

A disembodied woman’s voice speaks from two-thousand-million terrestrial years in the future: “We are the last men. We wish to communicate with you.” Tilda Swinton says, clear and steadily, that she’s from the 18th species of post-humanity. She has an urgent message concerning our future, viewed from the perspective of post-human life but she only delivers that message during the last minutes of this audio-visual essay.

We see no physical post-humans. Just more sculptures, some reminiscent of Stonehenge, except these appear to be made of cement blocks rather than huge stones. They are shot in varying tones of black and grey. Once there’s a splash of red when the narrator mentions the sun’s burning heat, and several times a green dot expands to a line to represent a radio signal. Otherwise, there’s no colour at all.

Last and First Men comments on human morality, mortality and legacy but it takes too long to make its point. In the last several minutes, Swinton says that astronomers have made a startling discovery that assigns a speedy end to humankind. “We can help you,” she says, “and we need your help.”

But, apart from suggesting her cohorts could travel back through time to adjust our behaviour so we don’t precipitate our extinction, nothing happens.

Last and First Men screens as part of the digital offerings at this year’s Vancouver International Film Festival through October 7. Visit viff.org for tickets and information.