Plot that failed? Good: prisoner taken in below (9)
I believe the answer is:
gunpowder
'plot that failed?' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
'good prisoner taken in below' is the wordplay.
'good' becomes 'g' (abbreviation).
'prisoner' becomes 'pow' (POW is an example).
'taken in' is an insertion indicator.
'below' becomes 'under' (synonyms).
'pow' inserted into 'under' is 'unpowder'.
'g'+'unpowder'='GUNPOWDER'
Can you help me to learn more?
(Other definitions for gunpowder that I've seen before include "Explosive chemical mixture" , "Explosive mixture (of tea?)" , "and 24: 1605 conspiracy" , "Explosive; type of 23 dn" , "It's used in gunnery and fireworks" .)