Sweet Sweetback’s Baadasssss Song (1971) Directed by Melvin Van Peebles

From Wikipedia: Because Van Peebles couldn’t afford a stunt man, he performed all of the stunts himself, which also included appearing in several unsimulated sex scenes. At one point in the shoot, Van Peebles was forced to jump off a bridge. Bob Maxwell later stated, “Well, that’s great, Mel, but let’s do it again.” Van Peebles ended up performing the stunt nine times. Van Peebles contracted gonorrhea when filming one of the many sex scenes, and successfully applied to the director’s guild in order to get workers’ compensation because he was “hurt on the job.” Van Peebles used the money to purchase more film.

Van Peebles and several key crew members were armed because it was dangerous to attempt to create a film without the support of the union. One day, Van Peebles looked for his gun, and failed to find it. Van Peebles found out that someone had put it in the prop box. When they filmed the scene in which Beetle is interrogated by police, who fire a gun next to both of his ears, it was feared that the real gun would be picked up instead of the prop. While shooting a sequence with members of the Hells Angels, one of the bikers told Van Peebles they wanted to leave; Van Peebles responded by telling them they were paid to shoot until the scene was over. The biker took out a knife and started cleaning his fingernails with it. In response, Van Peebles snapped his fingers, and his crewmembers were standing there with rifles. The bikers stayed to shoot the scene.