The movie's title, Don't Think I've Forgotten, was taken from a famous Sinn Sisamouth song of the same name.
When it comes to Cambodian music, many people are familiar with contemporary pop songs or some of the more traditional stuff.
Far less familiar is the country's rock 'n' roll scene of the 1960s and 70s, when performers infused traditional Cambodian music with power rock rhythms from the West, creating a rare and original soundtrack to the defining decades of modern Cambodian history.
It's a subject that American film-maker John Pirozzi attempts to capture in his yet to be released documentary, "Don't Think I've Forgotten: Cambodia's Lost Rock and Roll."
It was a time when the country's most prized voices — Ros Sereysothea, Sinn Sisamouth, Pan Ron and Huy Meas, to name but a few — boomed from the clubs of Phnom Penh and blared across the radio airwaves from Ratanakkiri to Koh Kong.
Yet for all its musical magnificence, the story of Cambodia's rock 'n' roll scene is nearly forgotten, Pirozzi says.
"It just seemed like an interesting story that hasn't been told," he explains of the movie's inspiration during a telephone interview from Pennsylvania, in the United States.
Pirozzi is no stranger to Cambodia. He is married to Linda Saphan, a Cambodian-born artist who did research for the documentary. He was the camera operator for "City of Ghosts," a 2002 feature film shot in Cambodia and directed by Matt Dillon, who also starred in the movie.
"Don't Think I've Forgotten" is still unfinished. Editing, a long and arduous process for any feature-length film, still needs to be completed. Pirozzi conducted more than 70 interviews. He spoke with many of the musicians who played during the 60s and 70s. Some still live in Cambodia, but many have moved abroad to France, the United States and elsewhere. In the process, Pirozzi amassed nearly 150 hours of filmed interviews in three different languages — Khmer, English and French.
He spoke with two sisters of the late pop starlet Ros Sereysothea, who disappeared under the Khmer Rouge regime.
"They had very good memories of her," Pirozzi says, noting that Ros Sereysothea's mother used to watch many of her daughter's shows.
The Western-influenced rock 'n' roll scene in Cambodia stretches back as far as the early 1960s, when such hits as "The Twist" were popular, Pirozzi explains.
Pirozzi and his film crew pose with Sieng Vanthy, former lead singer of the 70s super group SKD.
Long hair for guys and bell-bottoms soon followed, and the scene continued to flourish until 1975 when the Khmer Rouge came to power and went about systematically wiping out all traces of Western influence.
Still, there was a vibrant rock scene in place for over a decade.
"The middle class, upper middle class and rich kids were pushing the boundaries," Pirozzi says.
Sinn Sisamouth started out as a "crooner and big band guy" in the 50s and continued to be a prominent figure for the duration of the rock 'n' roll scene, he points out.
"I always saw him as an Elvis Presley of Cambodia," Pirozzi says.
Pirozzi recently screened a rough-cut of his film at a local movie house in Phnom Penh. The response was "overwhelming," he says. The final cut should be finished by January, if everything goes smoothly. And if Pirozzi can raise more money, which he admits has been difficult.
Traveling around the globe to interview people for the film has been daunting, not to mention expensive. But for reasons not always easily explainable, the native New Yorker says that Cambodia's music remains a story he just can't forget.
"Sometimes," he says, "I look in the mirror and say, 'I am crazy'."