Making movies can be a dangerous business. Actors rely on stunt performers to do the really hard stuff, but it doesn’t mean everyone on set is safe. Over the years, we’ve heard about accidents on film sets that can cost production time and delay schedules. If we’re lucky, it’s a minor inconvenience and no one is seriously hurt or killed. Unfortunately, that’s not always the case. Many stunt performers have been critically injured and even tragically lost their lives while working on some of your favorite movies.

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Tragedies aren’t sequestered just to the stunts, though. Sometimes horrible accidents can lead to the death of others on set. Cameramen, crewmembers, and even extras aren’t immune to some of the most dangerous work in the world. Even the actors themselves can end up in the hospital for long stretches of time. On a few occasions, television and voice actors have died during the filming of their shows, leaving their coworkers to mourn their untimely passing. Here are 15 real-life tragedies that have befallen superhero TV and movie sets. Many of these people lost their lives producing some of the most entertaining movies around, so it’s only right that we remember them and thank them for everything they did.

15 HEATH LEDGER (THE DARK KNIGHT)

The Dark Knight's Joker holds up a joker card

After some initial misgivings, comic book fans everywhere grew excited to see Heath Ledger’s intriguing portrayal of the Joker in 2008’s The Dark Knight. Just as marketing for the film was heating up, things took a tragic turn when news broke that Ledger had died in his hotel room from a combination of prescriptions drugs.

After Ledger’s passing, it became clear that the 28-year-old actor had struggled with the dark nature of his role, and it left him feeling depressed. Ledger had since moved on to film The Imaginarium of Doctor Parnassus while The Dark Knight was completed in post-production, but he was not the same. The film ultimately proved to be a massive success, and Ledger’s performance was widely praised. It ended up earning him an Academy Award for Best Supporting Actor.

14 CHARLIZE THERON (AEON FLUX)

Before the 2005 science fiction action film Aeon Flux was ever a box office bust, it nearly took the life of its lead actress. Charlize Theron, cast as the titular character, suffered a devastating injury just 10 days into filming. While performing her own stunt work that required her to complete a series of back flips, the actress landed awkwardly on her neck.

Theron went to the hospital, where she learned she had a herniated disc that nearly left her with permanent limited mobility. Doctors were unsure if she would recover, but she returned to work after weeks of physiotherapy. Since then, she has been outspoken about her previous decision to do her own stunts and is now happy to let the professionals do the work.

13 SET DRESSER (JUMPER)

The 2008 film Jumper, based on the 1992 novel by Steven Gould, revolved around people who could teleport all across the world. As a result, director Doug Liman insisted that the movie have multiple sets on different continents. From December 2006 to January 2007, Jumper was on location in Toronto in the dead of winter. This ultimately cost a man his life.

While taking apart a set on January 26, 56-year-old set dresser David Ritchie was struck by frozen debris and killed. Another worker was injured and had to be sent to the hospital with serious injuries to his head and shoulder. According to the police investigation, frozen sand and earth that was attached to a wall for exterior design came unstuck and crushed Ritchie, killing him instantly.

12 CREWMEMBER (GI JOE: RETALIATION)

GI Joe Retaliation

The 2013 action film G.I. Joe: Retaliation suffered tragedy when the movie was on location in New Orleans. In November 2011, Mike Huber was working in a warehouse that had been converted to serve as a soundstage. While crewmembers were tearing down and changing out sets, he fell to his death.

At the time of the incident, Huber was working on a scissor lift when it toppled over for unknown reasons. The locally hired crewmember suffered critical injuries from the fall and ultimately died from his wounds. Film production companies put a lot of work into ensuring the safety of all actors and workers on set, but accidents can still happen. Even with all the precautions, it’s hard to say how this incident could have been avoided.

11 BRANDON LEE (THE CROW)

The Crow movie still.

One of the more famous on-set accidents led to the death of leading actor Brandon Lee in the 1994 film The Crow. A scene for the movie required actor Michael Massee to fire a .44 Magnum at Lee’s character. Improper preparation of the gun’s ammunition led to a bullet getting lodged inside the barrel. When Massee fired the gun, Lee was struck with an actual bullet, in place of the expected blank round.

Lee was shot in the abdomen and was rushed to the hospital, where he died following six hours of surgery. At the time of his death, the movie was mostly completed and only required a few more days of filming. A stunt performer was used as a body double for Lee’s remaining scenes.

10 STUNTMAN DIES (THE DARK KNIGHT)

Heath Ledger was not the only tragic death attached to The Dark Knight. Stunt technician Conway Wickliffe was killed in a car crash while planning a stunt with the Batmobile. The accident took place at the QinetiQ at Longcross near Chertsey, Surrey in September 2007.

At the time of the accident, the stunt crew was going through a test run for the scene where the Batmobile is blown up. Wickliffe was filming from a Nissan 4x4, which failed to make a required 90-degree turn. The car veered off the course and struck a glancing blow against a tree at 20 MPH. The 41-year-old crewmember took a direct hit and died from his injuries on the scene. The Dark Knight was dedicated to both Ledger and Wickliffe.

9 JAIMIE ALEXANDER (THOR: THE DARK WORLD)

Lady Sif Shield

While on the London set of Thor: The Dark World, Sif actress Jaimie Alexander suffered a devastating injury — and she wasn’t even filming a scene! In September 2012, Alexander slipped on a metal staircase in the rain, fell, and seriously injured herself. According to the actress, it was five in the morning, it was dark, and clearly things were a bit slippery. That’s a recipe for disaster.

Alexander suffered a slipped disc, chipped 11 vertebrae, dislocated her shoulder, and tore her rhomboid muscle. The injuries to her body were so severe that she missed several months of filming while healing and rehabbing. This just goes to show you how dangerous a movie set can be, even when the actors aren’t filming. She’s lucky to still be alive and able to continue her career, and so are we!

8 MULTIPLE ACCIDENTS (RESIDENT EVIL: THE FINAL CHAPTER)

Resident Evil: The Final Chapter was meant to bring Milla Jovovich’s run as Alice to an end, but its legacy will forever be marred by on-set accidents. While filming a motorcycle stunt scene, British stuntwoman Olivia Jackson crashed into a camera crane that failed to lift out of her way. As a result, she was in a medically-induced coma for two weeks and ultimately lost her arm in December 2015.

Another accident occurred on set that took the life of crew member Ricardo Cornelius. A U.S. Army issue Hummer had been on a rotating platform, but fell off and pinned Cornelius against a wall. He later died of his injuries at the hospital. Sometimes it just goes to show you that some movies are just too dangerous to even be worth making.

7 LINA GARY (SPIDER-MAN)

09 Aunt May Spider-Man Animated 1994

Lina Gary was a successful voice actor who had lent her voice to several comic book cartoon shows before she was cast as Aunt May for the 1981 Spider-Man animated series. The show only lasted 26 episodes before giving way to the more popular Spider-Man and his Amazing Friends, but when it came time to cast for the 1994 Spider-Man: The Animated Series, the producers asked Gary to reprise her role as Peter Parker’s guardian.

Gary provided the voice of Aunt May for the first season until she passed away from brain cancer at the age of 50 in 1995. Voice actress Julie Bennett was cast to replace Gary in the role, which she held through 1998 for the show’s next four seasons on the air.

6 EXTRA INJURED (TRANSFORMERS: DARK OF THE MOON)

Transformers Dark of the Moon

Transformers: Dark of the Moon turned disastrous in September 2010 when an extra was seriously injured on the set. While filming on a highway in Hammond, Indiana, a steel cable holding a car being towed snapped in the middle of a stunt and struck an extra’s car. Gabriela Cedillo was hit so hard that she was rushed to the hospital and had to undergo emergency brain surgery. This should tell you just how dangerous the stunt actually was.

Cedillo was left with permanent brain damage, paralysis on the left side of her body, and an injured eye. Paramount supported Cedillo through it all, paying for her medical bills and admitting responsibility for the accident. Nonetheless, the Cedillo family filed a lawsuit against the company and was eventually awarded an $18 million settlement in 2012.

5 DIVER DROWNS (THE LONE RANGER)

The set of The Lone Ranger was plagued by all sorts of problems throughout production, but things took a tragic turn when a crewmember died in September 2012. At the time of his death, 48-year-old Michael Andrew Bridger was prepping a pool in the desert outside of Los Angeles that was to be used for an underwater scene near the end of the film.

Crewmembers on the set were able to pull Bridger from the water, and he was airlifted to a nearby hospital, but he was ultimately pronounced dead. According to the police investigation, Bridger was wearing full scuba equipment to clean the pool when he suffered a massive heart attack and ended up drowning when he was unable to get out of the water.

4 JOHN HAMILTON (ADVENTURES OF SUPERMAN)

Actor John Hamilton is best known for his portrayal of newspaper editor Perry White in the 1950s TV series Adventures of Superman. He appeared in all six seasons of the show’s run between 1952 to 1958. Few people remember, however, that he died before Adventures of Superman had finished its run on the air.

When the 71-year-old actor passed away, the producers of the show had plans to continue the series for at least another two years. Hamilton’s death delayed filming before Pierre Watkin was cast to replace Hamilton as the brother of Perry White. Watkin had already played White in the two Columbia serials, so it was a natural fit. The show would have continued on like this if Superman actor George Reeves hadn’t suddenly died and brought everything to a screeching halt.

3 ROGER C. CARMEL (TRANSFORMERS)

2-Mudd-Star-Trek-Villains

Roger C. Carmel, the actor popularly remembered for his role as Harry Mudd on Star Trek, began a successful voice acting career in the late 1980s. After reprising his role on Star Trek: The Animated Series in 1977, he also took on roles in several children’s cartoon shows, including the original Transformers television series.

Carmel was credited with 32 episodes between 1985 to 1987, chiefly voicing Bruticus and Cyclonus. Unfortunately, he passed away in 1986 at the age of 54 prior to the show’s fourth season. As a result, Bruticus would no longer appear and Jack Angel was cast as Cyclonus for the final season. Carmel was also set to reprise his role as Harry Mudd on Star Trek: The Next Generation, but he passed away before filming could start.

2 GEORGE REEVES (ADVENTURES OF SUPERMAN)

George Reeves as Superman on I Love Lucy.

George Reeves was Superman on the Adventures of Superman television show from 1952 right up to his death in 1959. On June 16, 1959, it was discovered that Reeves had taken his own life with a single gunshot to the head. At the time of his death, the producers of the series had plans to continue the show for another two seasons.

His death was ultimately ruled a suicide, but inconsistencies in the police report and general hearsay have led to a number of conspiracy theories surrounding the incident. Some believe that Reeves was murdered by his fiance Leonore Lemmon and others believe MGM vice president Eddie Mannix, who had mafia ties, had him killed for having an affair with his wife. In 2006, the film Hollywoodland was released about the incident with Ben Affleck playing George Reeves.

1 STUNTWOMAN DIES (DEADPOOL 2)

Zazie Beetz as Domino in Deadpool 2

Deadpool 2 was hit with controversy when stuntwoman SJ Harris was killed while performing a motorcycle stunt in August 2017. She didn’t wear a helmet for the stunt because Domino, the character she was doubling for, doesn’t wear a helmet in the scene. Instead of taking the time to create a helmet for her that could fit under the Domino wig, an accelerated filming schedule required them to do the stunt without one.

The decision to cast Harris was also criticized by multiple stunt professionals. She was the first African-American female professional road racer, but she was an inexperienced stunt performer. With reports of long and exhausting hours of filming on set, the cause of the tragedy was heavily criticized, as was the too-soon loss of Harris.

Did we miss an incident? Let us know in the comment section.