"It was happening on the main floor at the [theatre]. And the music had started to play to get back in our seats. The people around us were saying, 'Not here! Not here!' Like it was okay to fight in the parking lot, you know, but it was not okay there when the music was playing, and they were about to go live."
Cameron explained that the cause of the fight was the director Guillermo del Toro (Pan's Labyrinth, Hellboy), who had clashed with Weinstein and his brother Bob several months earlier.
"It's kind of a long story, but it has to do with Guillermo del Toro and how badly he was dealt with by Miramax on [the 1997 cockroach horror picture] Mimic," Cameron remembered.
"Harvey came up glad-handing me, talking about how great they were for the artist, and I just read him chapter and verse about how great I thought he was for the artist based on my friend's experience, and that led to an altercation."
Del Toro's chequered history with the Weinsteins is well documented. The Mexican director clashing with the pair on the set of Mimic, which was his first American film.
The feud escalated to such an extent that Bob Weinstein, then head of Miramax's sister studio Dimension Films, tried to get him fired.
When Weinstein saw early footage from the film in 1997, he complained that the scenes weren't scary enough, and that the tone was wrong. He eventually barged onto the Toronto set, trying to instruct del Toro how to direct a movie. He then decided he had to fire him.
"Maybe we're making two different movies," del Toro said, as published in Peter Biskind's Down and Dirty Pictures: Miramax, Sundance, and the Rise of Independent Film.
"No, you're not making a good movie," was Weinstein's reply. "You're going home tonight, we're gonna pick up the pieces tomorrow with somebody else."
It was only an intervention from Mimic's leading lady Mira Sorvino that led to del Toro staying put.
The actress, who had just won an Oscar for her role in the Miramax film Mighty Aphrodite, threatened to pull out of the film if del Toro's vision wasn't respected, and even roped her then-boyfriend Quentin Tarantino, Miramax's former golden child, into defending her director.
Eventually the Weinsteins backed down, but still insisted on getting final cut on the film.