Nit-Witty Kitty is a 1951 animated short that is the 61st Tom and Jerry cartoon. It is a ridiculous, but very memorable and positively weird entry.
Tom gets amnesia and believes that he is a mouse now. Jerry, frustrated, attempts to hit his head with various means in order to bring him to his former self. Yes, this entry is the most cartoony Tom and Jerry short ever and although it was sometimes too ridiculous and also convenient with Jerry not trying hard enough, I still found it to be incredibly entertaining and quite unique.
It is different than any entry up to this point as it entirely shifts the roles between the cat and the mouse. But it also has a great use of Mammy Two Shoes with the ending being just fantastic. But I really liked the action here, the over-the-top cartoony sound effects are fun and the short is extremely entertaining and quite funny at times. It is also for the most time positively weird. It takes time to adjust to it, but I respect the series for still managing to contain some fresh and original ideas after more than a decade of films.