Thirty years ago this week, a Hollywood star was decapitated while shooting a scene for a movie. The actor was Vic Morrow, the veteran star of the TV series Combat. He was killed, along with child actors Renee Chen and Myca Dinh Le, by a falling helicopter during filming of The Twilight Zone, a feature-length adaptation of Rod Serling’s television series.

Morrow played a bigot who skipped through time getting a taste of his own medicine. In the scene that would prove fatal, he was earning some Serling-style redemption by trying to rescue a pair of Vietnamese children from an American air raid. Mainly, the setup was an excuse for director John Landis to capture immense explosions on film.

At the controls of the helicopter that was “bombing” the village was Dorcey Wingo, an actual Vietnam veteran. Wingo was new to the movie business, so even when the rehearsal explosions that buffeted his chopper scared him witless, he swallowed his concerns, especially as Landis, who had a reputation for being dictatorial on set, screamed expletives into the California night. (The shooting was taking place at a disused motorcycle track at Indian Dunes Park, a few miles north of Los Angeles.)

When the cameras rolled, pyrotechnic fireballs engulfed Wingo’s helicopter, forcing him down into a river where the actors waded. As a hundred or so people looked on, the right skid of the aircraft crushed 6-year-old Renee, who was a few feet from Morrow (the aging star had dropped her). The helicopter then toppled over, and its main blade sliced through Morrow and 7-year-old Myca. According to Stephen Farber and Marc Green’s exhaustive book on the incident, Outrageous Conduct, there was shocked silence until Renee’s mother started shrieking as she kneeled over her daughter’s lifeless body. Morrow never got to deliver his scripted line: “I’ll keep you safe, kids. I promise. Nothing will hurt you, I swear to God.”

Civil suits against the studio and Landis were settled, but Warner Bros., Landis, Wingo, and three others couldn’t avoid criminal charges of involuntary manslaughter stemming from the tragedy. The defendants freely admitted that the production broke child labor laws, but they maintained that the crash was an unavoidable accident. After three years of legal wrangling, the suit finally went to trial in L.A. in 1985. Despite an emotional bit of prosecution by Deputy District Attorney Lee D’Agostino—she theatrically offered Landis tissues after he teared up during his testimony, hissed “murderer” at him in full view of reporters when he happened to walk past outside the courtroom, and summed up her case by booming, “It isn’t that John Landis decided to violate the law, it’s that he thinks he’s above it!”—she failed to win a conviction. Landis and his co-defendants were acquitted of serious charges, and the director went on to make Coming to America, a hit that put the tragedy in his rearview mirror.

Terrible as the Twilight Zone accident was, some good did come of it. At Warner Bros., a behind-the-scenes revolution was set in motion, as a vice president named John Silvia was determined to tighten up the industry’s approach to safety. Silvia convened a committee that created standards for every aspect of filmmaking, from gunfire to fixed-wing aircraft to smoke and pyrotechnics. All the unions and guilds in the business were represented. “It was like lawmaking,” says Chris Palmer, a risk-management consultant who was part of the committee. “The committee had to parse words like ‘would, shall, and must’ because of the possibility of negligence lawsuits overtaking Hollywood if they were too strict in the wording.” The committee’s codicils were collected into a group of standards called Safety Bulletins. The studios then issued a manual to their employees based on the bulletins, known as the Injury and Illness Prevention Program. (The guidelines have been updated over the years and are now digitized—the current versions can be found here.)

It wasn’t an overnight process, and the standards needed continual updates—despite increased efforts to improve safely, accidents kept happening. Veteran pilot Art Scholl was killed when his camera plane crashed during the filming of Top Gun; stuntman Reid Rendell was killed in a helicopter crash on the set of Airwolf; actors Brandon Lee (Bruce’s son) and Jon-Erik Hexum (star of the NBC series Voyagers!) were killed by guns loaded with blanks.

New Safety Bulletins were issued after each mishap. When legendary stuntman Dar Robinson died in a remote area after rupturing his spleen in a stunt during the shooting of Million Dollar Mystery, on-set ambulances became mandatory. The process continues today. “With every accident comes more regulations,” says Pam Elliott, production manager at Special Effects Unlimited, a longtime provider of explosives and other effects for Hollywood. “Every time someone gets hurt, we learn, and rules are put in place to try to make sure it doesn’t happen again.”

The insurance industry made sure that safety provisions stuck. Before The Twilight Zone, insurance companies didn’t view the movie business as a source of profit: Given how unsafe film sets were, the likelihood of a payout was just too high. Afterward, the industry’s commitment to improving safety, along with increasing budgets, made Hollywood a better risk. Soon, getting affordable rates to underwrite shoots became a basic part of the movie-making business. And that meant dancing to the insurance industry’s tune. “The insurance companies want to know everything,” Elliott says. “They want your resume, the resumes of everyone participating. They want to see your licensing, a list of materials, the number of people working on each shot, the distance they will each be from the explosive, the number of fire extinguishers available on set. Then the fire department comes out to look at what you’re doing, and they have a long list of safety criteria to meet, too. It’s a pain in the butt, sure, but that’s the way it is.”

Perhaps the biggest evolution took place in the field of risk management. “The Twilight Zone accident created my job,” says Palmer, who has assessed the risk involved on shoots ranging from Titanic to X-Men to Speed 2. “It was a sea change in the movie industry. No one in risk management was ever on set before then.” As opposed to insurance, which finances risk, risk consultants attempt to avoid it, or at least control it. Risk managers like Palmer become involved in a film long before principal photography begins, scanning scripts for issues, starting with the location. “If you want to shoot in the Caribbean during hurricane season,” Palmer says, “you’ve got a problem, unless you have a specific plan in place to protect the production.”

On set, Palmer’s job is to step in when crew members want to play it safe but feel their careers would be in jeopardy if they spoke up. “I can’t be terminated by the director or producer. … That takes the pressure off the crew because it can be intimidating to be the one to stand up and say ‘hold on.’ ” Had Palmer or one of his colleagues been on the set of The Twilight Zone, Dorcey Wingo’s concerns might have stopped filming. “Wingo was a remarkably talented pilot—but he wasn’t a movie pilot,” Palmer says. “Senior movie pilots would have taken their helicopter and gone home.” But the potential consequences weighed heavily on a guy who wanted to have a showbiz career.

(And Landis had bullied his way through The Twilight Zone: According to Outrageous Conduct, the director grew frustrated as lighting the fatal scene grew difficult. The job required grips to climb scaffolding thirty feet in the air while being buffeted by rotor wash from the helicopter. When some techs hesitated, Landis demanded, “Is there somebody on this electrical crew who’s not too chickenshit to do the job?”)

The rise of computer-generated imagery has taken a lot of the danger out of stunts, especially stunts involving explosions. But movie sets can still be dangerous places. While filming the recent superhero flop Green Lantern in Louisiana in July 2010, pyrotechnical effects worker John Franco was injured by a van that was sent hurtling through the air as part of a shot. According to Franco’s negligence lawsuit against (ironically enough) Warner Bros., director Martin Campbell added the stunt during shooting, meaning it wasn’t in the script. Franco alleges that the van was damaged in rehearsals but was used within the hour in the name of expediency. Sure enough, it broke apart, causing Franco “lifelong-affecting (sic) injuries.”

Hopefully the safety regimens put in place after the deaths of Morrow, Renee, and Myca 30 years ago will keep any accidents from befalling the cast and crew of another Warner Bros. production that the studio hopes to mount as soon as it has a viable script: a remake of The Twilight Zone.