1.In The Princess Diaries, the scene when Mia slipped and fell on the bleachers was unplanned. The scene was shot on top of a school in San Francisco when it was raining. Heather Matarazzo told Cosmopolitan, "That's Annie in a nutshell: You fall, you laugh, and you keep going. And that's what ended up in the film."
2.In Django Unchained, Leonardo DiCaprio cut his hand when he slammed it on a table and accidentally smashed a glass. He continued the scene. "My hand started really pouring blood all over the table," said DiCaprio.
3.In Fast & Furious 6, Tyrese tells The Rock's character to "hide your baby oil," The Rock ad-libbed back, "You better hide that big-ass forehead." This line caused Ludacris to genuinely spit out his drink in laughter.
4.In The Hateful Eight, Kurt Russel accidentally destroyed an 1870s antique guitar that was on loan from the Martin Guitar Museum. When he smashes the guitar, Jennifer Jason Leigh's reaction is genuine.
5.The logistics behind the famous chestburster scene in Alien were kept secret from the actors, in hopes of drawing genuine horrified reactions from them. Veronica Cartwright, who played Joan Lambert in the film, passed out when she was splattered with blood.
6.Choi Min-sik, star of the Korean film Oldboy, had to eat four whole living octopi on camera before the director captured the perfect shot. Min-sik is also a Buddhist, and would pray for forgiveness after each take.
7.In The Lord of the Rings: The Two Towers, Viggo Mortensen screamed in agony after kicking a helmet, that played well into the stark scene. In reality, Mortensen had broken two toes and was howling in pain.
8.At the end of Casino, Joe Pesci is beaten with baseball bats in a cornfield. According to Pesci, he broke a rib when two "heifers" fell on him the wrong way. According to Pesci, director Martin Scorsese yelled at him to "be in the moment." The take was ultimately used in the final cut of the film.
9.While filming a mental breakdown in a hotel room for Foxcatcher, Channing Tatum was supposed to smash his head into a prop mirror. He smashed the mirror so hard, he also broke the wall behind it. He started bleeding profusely from his forehead, but continued to perform the scene.
10.Martin Sheen was "so hopelessly drunk" for the opening scene in Apocalypse Now that takes place in a Saigon hotel. The actor punched a mirror and cut his hand. He continued the scene, smearing blood on his face and on the sheets.
11.Because the mechanical birds failed to work on set, real birds were used in Alfred Hitchcock's The Birds. Tippi Hedren endured through five days of handlers hurling ravens, doves, and pigeons at her. “It was brutal and ugly and relentless,” said Hedren.
12.Jackie Cooper was eight when he starred in the 1931 film Skippy. When Jackie couldn't summon tears for a scene, director Norman Taurog removed Jackie's pet dog from the set and pretended to have it shot. This caused Jackie to cry hysterically and deliver a performance that earned him an Oscar nomination.
13.Tony Todd, who played Candyman in the film by the same name, had actual bees in his mouth while filming the climactic scene. He wore a throat guard for protection and was not stung. Virginia Madsen had her face showered with live bees as well.
14.In The 40-Year-Old Virgin, Steve Carell actually had his chest hair waxed on camera. His incessant screaming and lines were all improvised on the spot. Behind the cameras, before filming the scene, he said, "I don't think it's gonna hurt at all."
15.In Blade Runner, Daryl Hannah's character, Pris, was supposed to run during a raining scene, but accidentally slipped on the wet pavement and jammed her arm into a car window made of real glass. She continued the scene as if nothing happened. Hannah chipped her elbow in eight different places and still has a scar.