Cryptic crossword clue
Ultimately, Marilyn Monroe had to appear ditzy — never mind! 2,4,4

The most common and most likely answer to this crossword clue is the 2 plus 4 plus 4 letter word NO HARM DONE

I've seen this crossword clue in The Guardian
N
O
H
A
R
M
D
O
N
E

Buddy explains!

The straight part
We know that "never mind" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case never mind = no harm done.
The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.
This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.

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