Crossword Genius

It's heard before getting off punishment, caught in plots with politician (7,5)

Ross

I believe the answer is:

bedtime story

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'it's heard before getting off' is the definition.
I can't tell whether this defines the answer.

'punishment caught in plots with politician' is the wordplay.
'punishment' becomes 'time' (time in prison).
'caught in' is an insertion indicator.
'plots' becomes 'beds' (bed is a kind of plot).
'with' means one lot of letters go next to another.
'politician' becomes 'tory' (term for a Conservative Party politician).
'time' placed within 'beds' is 'bedtimes'.
'bedtimes'+'tory'='BEDTIME STORY'

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I've seen this clue in The Guardian.
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