The film was sparked by the older couple's announcement that they were going to pack up and leave the house of the title, where Duncan had lived until she was 10. That house, she explains, "contained all our lives" - the pre-teen Duncan's school photo puts in several appearances - and the idea of documenting it took hold.
"One thing that comes up repeatedly in my work is a sense of nostalgia. Chris Jannides [the founding director of the dance company Limbs], who was a real mentor, once said of my dance work that I was a nostalgic naturalist. And when my mother told me that she was going to move, I had this real shock.
"All my memories of identity were embedded in the physical objects of the house. I wondered: what would I be without the physical traces of my existence."
Duncan planned a short experimental documentary in which the house was the main character and her parents - very reluctantly - agreed to be figures in the background, so that the house would not seem empty.
In the event, the real-life plan to leave the house was cancelled, but the movie-life plan stayed, says the film-maker. "I realised how interesting and curious these people were, who were not so much performing as being in their natural space but in a directed way."
The result is small but enchanting work, neither fact nor wholly fiction, in which the film-maker's autobiography - her sense of self, even - and her technique become indistinguishable.
"To me it's a sort of artisan approach," says Duncan, touching the clay cup from which she is drinking tea. "It's something that is conceptualised and formed in the way that you form a piece of Japanese pottery. You start off with the base clay - I do have parents who are a cross-cultural couple - but then I have to carve away and decide what it is that I am looking at."
Lee and Meng's reluctance to be background figures was nothing compared to their resistance to being the only characters. Duncan had to deploy all her powers of persuasion.
"They really didn't want to do it," she said. "I didn't show it to them until after I had been accepted into the [2012 Auckland] film festival.
"Taking it to them was the most fearful experience, because there was a lot of reluctance through the shooting process. And then I showed it to them and halfway through, my stepmother turned to me and said, 'It's a movie. It's a real movie. It's got ideas.' And I was," - she wipes her brow theatrically - "I was ... 'Phew'."
Who: Alyx Duncan
What: The Red House
When: At selected cinemas from today
Info: theredhousefilm.com
- TimeOut