Singin’ in the Rain (1952)
these men are such fundamentally different dancers but especially at slow GIF speed it’s clear how perfectly precise they were as a duo.
Donald O’Conner was actually nervous about this because he considered himself more of a hoofer than a dancer, and if you watch this number you can see he uses his upper body less than Gene Kelly. Also, they were both really worried that the other would turn the opposite direction from them, but as you can see, unlike Zoolander, they both turn left. :D