Marilyn...
This is one of Marilyn's most relaxed early performances. She is adorable here, and seems to be in the movie more than she is, because director Howard Hawks--he would guide her to even greater effect in "Gentlemen Prefer Blondes"--has her popping in and out all through "Monkey Business.". And for history's sake, Miss Laurel was her first truly "dumb blonde." She is just a old man's sweet mistress in "The Asphalt Jungle" and Miss Caswell in "All About Eve" is no dummy--just an actress on the make. Her other small roles afterward were manipulative blondes, but not stupid. In fact, no other MM character except the hillbilly "singer" Cherie in "Bus Stop" would be as dumb as Miss Laurel.
One cannot let the subject of MM go without commenting on her figure in "MB." She is a little plump, which I don't mind, and wears the most aggressive push-up bra of her career. Her bosoms--in the pleated dress with the fitted top--look like they are about to blast into outer space. It's funny how her voluptuous body said one thing, but her sweet face said something else entirely. She was a sex-symbol who didn't have much sex(onscreen) How could she? Who knew what to do and how to approach her with that conflicting persona? That's why her nameless "Girl" in "The Seven Year Itch" is the perfect role for how her image developed (tho not my favorite MM flick) She's an untouchable fantasy, to be looked at and to be desired, but never touched.
She is better when she is touched--as in "Niagara" or even "Bus Stop" (Tho in the latter, Cherie has clearly been through the mill!) But her movies rarely allowed her to play any kind of a real woman.