Jia's "Caught By The Tides" is a decades-spanning love story that is in competition for the Cannes Film Festival's illustrious Palme d'Or.
It is a meditative reflection on cinema, the passage of time, and the profound changes that China has experienced over the past 25 years.
Jia, 53, told AFP the decision to make his unorthodox film was prompted by the Covid-19 pandemic, which made filming in China difficult.
He decided to revisit footage shot over the past few decades, some of which was originally filmed without any specific purpose as Jia and his crew experimented with diverse techniques.
"While editing, I suddenly realised that I would have to consider all the footage I had shot over the past 20 years as potential material," he said.
"That's how this film was ultimately formed."
Roughly 10 scenes in the film have actually appeared in his previous films.
But, he insists, "for me, it's a new story, a new understanding of the world and a process of recreating a new character, Qiao Qiao."
The movie begins in the early 2000s in the grim and impoverished surrounds of northern Chinese city Datong, where Qiao Qiao (Zhao Tao) and Guao Bin (Li Zhubin) meet and fall in love.
Guao Bin decides to try his luck in another part of the rapidly industrialising country. Qiao Qiao initially waits, before leaving in pursuit of him.
The film hops forward, many years at a time.
'Before and after'
Qiao Qiao is played by Jia's wife, Zhao Tao, who has starred in many of his films.
Due to the unusual filmmaking method Zhao, along with other returning actors, ages by 20-odd years in real life as the narrative progresses.
A final section, set in contemporary China, was shot during the pandemic.
"I was a little restless," Zhao told AFP. "What worried me was not the present, but my past performances. I didn't remember how I had done it.
"But when I saw my previous clips in the editing room I realised that my worries could be dispelled. From my beginnings I was always lucky enough to put the character in the foreground."
Part of the film uses footage initially shot against the backdrop of the construction of the Three Gorges Dam.
That vast project, which displaced more than a million people, is a subject that has long fascinated Jia, epitomising China's warp-speed transformation in the early 21st century.
It was also the subject of his 2006 "Still Life", which launched Jia to greater international acclaim by winning the Golden Lion at the Venice Film Festival, and "Ash is Purest White".
For Jia, the completion of the film marks the end of that chapter of his career.
"On the one hand, this film represents a retrospective and a reconstruction of my past," he said.
"At the same time, I think it is an inevitable turn for everyone. I have the impression that the world has been divided into a before and after the 2000s."
