It may be nudity, but I'd hardly call it gratuitous. From Ecstasy.
I've always found that most classic film beauties—your Crawfords, your Hayworths, your etceteras—were at best interchangeable and, at worst, bland. While the men of old Hollywood never have trouble making an impression, their romantic leads were usually so underwritten, so overly made up, that they never had a chance. There are a few exceptions, however—Barbara Stanwyck, Judy Holliday, Veronica Lake—but most of them were so beautiful, so lively, that they were kept out of the really famous pictures, and aren't as famous today as they perhaps ought to be.
To that list, let's add Hedy Lamarr—the woman best remembered for being a punchline in Blazing Saddles. I wrote a post for Bullett today about Ms. Lamarr, an inventor who didn't mind getting naked on camera. On the sex scene from 1933's Ecstasy, which follows a nude romp through the forest in pursuit of a horse:
Though less thoroughly benippled, the ensuing sex scene is crackerjack. Lamarr and her stud kiss a bit, lie down, kiss some more, and then he drifts downward out of frame—what may be the earliest use of what would become an incredibly tired way of signifying oral funtimes. But while the camera would normally pan up and away, here it lingers on Lamarr, and we get to watch her go through the range of facial expressions induced by this rather intense blue collar orgasm. For her performance, Wikipedia tells us adorably, “The authenticity of passion was attained by the film director’s off-screen manipulation of a safety pin strategically poking her bottom.”
Click through for a link to what may be the oldest NSFW video you will ever see—excepting, perhaps, the really racist bits of Birth of a Nation, which I bet you wouldn't want your boss to catch you watching.