In the scene where Clark Gable is drunk and on a car, he eventually falls down. Marilyn Monroe runs over to him. She's wearing a low-cut, loose dress with no bra and her boobs pop out completely. At the movies you might blink and miss it, but with stop frame or slo-mo you get a clear look. Certainly unusual in back in 1961 and surely unintended, based on the rest of the movie.