For the “Make Em Laugh” number in Singin’ in the Rain, Gene Kelly asked Donald O’Connor to revive a trick he had done as a young dancer, running up a wall and completing a somersault. The number was so physically taxing that O’Connor, who smoked four packs of cigarettes a day at the time, went to bed (or may have been hospitalized, depending on the source) for a week after its completion, suffering from exhaustion and painful carpet burns. Unfortunately, an accident ruined all of the initial footage, so after a brief rest, O’Connor, ever the professional, agreed to do the difficult number all over again (x). 
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For the “Make Em Laugh” number in Singin’ in the Rain, Gene Kelly asked Donald O’Connor to revive a trick he had done as a young dancer, running up a wall and completing a somersault. The number was so physically taxing that O’Connor, who smoked four packs of cigarettes a day at the time, went to bed (or may have been hospitalized, depending on the source) for a week after its completion, suffering from exhaustion and painful carpet burns. Unfortunately, an accident ruined all of the initial footage, so after a brief rest, O’Connor, ever the professional, agreed to do the difficult number all over again (x). 
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For the “Make Em Laugh” number in Singin’ in the Rain, Gene Kelly asked Donald O’Connor to revive a trick he had done as a young dancer, running up a wall and completing a somersault. The number was so physically taxing that O’Connor, who smoked four packs of cigarettes a day at the time, went to bed (or may have been hospitalized, depending on the source) for a week after its completion, suffering from exhaustion and painful carpet burns. Unfortunately, an accident ruined all of the initial footage, so after a brief rest, O’Connor, ever the professional, agreed to do the difficult number all over again (x). 

Only 19 when cast in Singin’ in the Rain, Debbie Reynolds lived with her parents and commuted to the set. She had to wake up at 4:00 a.m. and ride three different buses to the studio; sometimes, to avoid the commute, she would just sleep on the set. Her co-star and director, Gene Kelly, also insulted her for not being able to dance. Fred Astaire, who was hanging around the studio, found Reynolds crying under a piano and helped her with her dancing. After the actors finished the “Good Morning” number, Reynolds had to be carried to her dressing room because she had burst some blood vessels in her feet. Despite her hard work on the number, Gene Kelly decided that someone should dub her tap sounds, so he went into a dubbing room to dub the sound of her feet as well as his own. Reynolds remarked many years later that making this movie and surviving childbirth were the two hardest things she’s ever had to do (x). 
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Only 19 when cast in Singin’ in the Rain, Debbie Reynolds lived with her parents and commuted to the set. She had to wake up at 4:00 a.m. and ride three different buses to the studio; sometimes, to avoid the commute, she would just sleep on the set. Her co-star and director, Gene Kelly, also insulted her for not being able to dance. Fred Astaire, who was hanging around the studio, found Reynolds crying under a piano and helped her with her dancing. After the actors finished the “Good Morning” number, Reynolds had to be carried to her dressing room because she had burst some blood vessels in her feet. Despite her hard work on the number, Gene Kelly decided that someone should dub her tap sounds, so he went into a dubbing room to dub the sound of her feet as well as his own. Reynolds remarked many years later that making this movie and surviving childbirth were the two hardest things she’s ever had to do (x). 
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Only 19 when cast in Singin’ in the Rain, Debbie Reynolds lived with her parents and commuted to the set. She had to wake up at 4:00 a.m. and ride three different buses to the studio; sometimes, to avoid the commute, she would just sleep on the set. Her co-star and director, Gene Kelly, also insulted her for not being able to dance. Fred Astaire, who was hanging around the studio, found Reynolds crying under a piano and helped her with her dancing. After the actors finished the “Good Morning” number, Reynolds had to be carried to her dressing room because she had burst some blood vessels in her feet. Despite her hard work on the number, Gene Kelly decided that someone should dub her tap sounds, so he went into a dubbing room to dub the sound of her feet as well as his own. Reynolds remarked many years later that making this movie and surviving childbirth were the two hardest things she’s ever had to do (x).