The most common and most likely answer to this crossword clue is the 9 letter word MELODRAMA
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More clues leading to the result MELODRAMA
- Cast made moral sentiment the focus here?
- Histrionics alarmed Mo terribly
- Genial-sounding, taking small drink before a production
- Model stumbling – damage after twisting – a scene that’s overwrought
- Histrionics from a Spice Girl playing a dame briefly or . . . .
- Mother screening terribly drole theatrical performance
- Master a mad role, performing in sensational play
- Play short tune, hit by American
- Mother takes in role performing with daughter in sensational theatrics
- Mother describing older doctor’s excessively theatrical behaviour
Buddy explains!

The straight part
We know that "Overacting" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case overacting = melodrama.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.
What does MELODRAMA mean?
MELODRAMA noun- A kind of drama having a musical accompaniment to intensify the effect of certain scenes.
- A drama abounding in romantic sentiment and agonizing situations, with a musical accompaniment only in parts which are especially thrilling or pathetic. In opera, a passage in which the orchestra plays a somewhat descriptive accompaniment, while the actor speaks
- Any situation or action which is blown out of proportion.