Actors who dare to execute their own stunts garner the admiration of their audiences, and even their peers, the world over. Exhibiting such courage and physical prowess is not only tough as nails, but it can also take a character’s authenticity up a few notches–and sometimes even off the charts. The ambition and grit required to pull off the challenging and risky stunts, however, can be met with injury at any moment–and at times, serious injury. Here are two daredevil actors whose injuries can be added to the long, ever-growing list of on-set mishaps: Tom Cruise and Charlize Theron.

Tom Cruise

Recently on a London set, Tom Cruise took a brave leap across buildings while portraying Ethan Hunt for Mission Impossible 6. The 55-year-old actor attempted to run and jump from a rigging onto a nearby building but fell just short of the mark. Unfortunately, the megastar slammed into the side of the building hard. He reportedly attempted the stunt at least twice–both times meeting the same fate.

Although Cruise was strapped to a harness for protection, it didn’t seem to help in reducing the impact. The actor was clearly seen limping, writhing in pain, and holding his knee before being assisted by the on-set safety team. There are still questions about his condition and if production will need to be postponed for the action-thriller.

Cruise is famous for performing his own death-defying stunts including treacherous rock climbs, outrageous motorcycle chases, scaling the world’s tallest building, and dangling from a flying airplane. Sadly, the recent mishap occurred shortly after Mission Impossible 6 producer David Ellison, told Collider: “What Tom is doing in this movie I believe will top anything that’s come before. It is absolutely unbelievable–he’s been training for a year.” Now many people are questioning if it might be unwise for a man Tom’s age to be performing such insane stunts. The film is currently set for a July 2018 release date.

Charlize Theron

Charlize Theron was driven to make her empowered femme fatale character Lorraine Broughton as real as possible. With the Atomic Blonde protagonist being a top-level MI6 field agent and highly trained fighter, the Oscar-winning star knew she was going to have to pull off long and brutally raw action scenes–and do it believably. The 42-year-old actress knew she’d be taking a lot of hits on set–and giving them as well–in the Cold War spy thriller.

“I trained for the whole film about two-and-a-half months just to get my body to have some sort of muscle memory where I could just fight instead of just learning steps,” Theron said. She hit the gym for hours on end everyday learning Judo and other martial arts disciplines, and physically pressing the envelope. When the star would return home to her two young children, she’d sit down after being punched, kicked, and thrown into walls, and nurse her prodigious wounds. “Picking up my kid felt like picking up a mountain,” she said.

But that wasn’t the worst of it. Indeed, the pain was just starting. Theron explains, “When I trained, I actually cracked two teeth in the back of my mouth clenching while fighting because apparently, my arm strength wasn’t strong enough.” She told Xpose it was self-inflicted: “I think it was pure panic,” emphasizing the pressure she felt to pull off the brutally athletic feats for her passion project–wearing six-inch heels to boot! Needing to have her teeth removed, she went in for dental surgery right before traveling to Berlin to shoot the film.

Theron is still in the process of dealing with her teeth, but at least she’s no longer in agonizing, chronic pain. “I’m going in for my fourth root canal,” she said.

Charlize has had her share of on-set injuries. During the production of Snow White and the Huntsman, she screamed so much one night that she tore a stomach muscle. And she experienced a frightful injury during the making of Aeon Flux. Specifically, she suffered a herniated disc while performing a series of back flips and was almost left paralyzed. As a result, she had to wear a neck brace for months.