Dying Dennis Hopper among the stars of Las Vegas film project

A belgian film-maker who secretly recorded crowds in Las Vegas with a hand-held camera has captured the final movie appearance of the late Dennis Hopper.

Nicolas Provost's arthouse film, screened at Venice Film Festival, primarily features unassuming members of the public in bars, casinos and restaurants, and captured with a surveillance-style filming technique. But it also contains star turns from veteran Hollywood actors Jon Voight and Jack Nicholson, as well as Hopper.

Yesterday, Provost said he wanted to blur the lines between reality and fiction with his film, entitled Stardust – so much so, in fact, that he was unwilling to divulge whether he had stumbled across the highly paid actors accidentally and filmed them in secret, or if he was responsible for directing their every action.

He was also refused to divulge how much the actors were paid, if at all, although he insisted the film was "very low-budget". He admitted Hopper was in on the secret and had been very open to the concept of the film.

"It is very important that I don't reveal how I filmed them, but I will just say it is not all found footage [gained covertly]," he said. "I directed some of them; some was accidental. I filmed it last summer and, with Dennis Hopper, it was a wonderful encounter. It was striking how warm he was as a person."

Provost, who shot the entirety of his no-frills, one-man production in just two weeks, said he had not known that Hopper – who died of prostrate cancer in May – was ill. "I wasn't aware that I might have been filming him for the last time," he added.

He had hoped to send a copy of the completed movie to Hopper but did not manage to do so before his death. All three actors appear repeatedly, sitting or moving among the crowd. Hopper is first shown in a branch of McDonald's, while Nicholson walks around a hotel lobby, opening his arms and smiling menacingly, as the camera pans across the crowds.

The soundtrack incorporates ominous music and gunshots muffled by silencers, and the images range from scenes of Las Vegas glamour – bright lights, rollercoasters and smiling tourists – to more threatening visions of blacked-out limousines creeping along dark roads, and men smoking cigars or making surreptitious phone calls in murky corners, conveying a sense of dread and criminality.

Provost said he filmed throughout the city without being observed. "I had a very discreet, hand-held camera which I sometimes put on an aeroplane cushion instead of a tripod or on a garbage bin or table. In casinos, I worked with a smaller, hidden high-definition camera. In editing it, I introduced different crime stories and intrigues." The film has been dubbed so that any real conversations are unheard. Instead, the audio includes lines sampled from famous films, spoken by the well-known voices of Robert DeNiro and Al Pacino, which refer to mysterious murders, a criminal underworld, kidnappings and extortion.

Provost, whose artwork has been exhibited at the Berlinale exhibition in Germany, Seattle Art Museum in the US and across Europe, is working on his first feature-length film, The Invader, starring Stefania Rocca, who recently appeared with Willem Dafoe in A Woman, which also premiered at Venice this year.

Provost wants to transform his 20-minute film starring Hopper into a feature-length production. He intends to incorporate it into a trilogy with his other covertly-shot projects, which began with 2007's Plot Point – a fictional thriller filmed on the crowded streets of New York City.