Was about to be involved in (9)
I believe the answer is:
concerned
'involved in' is the definition.
'concerned' can be an answer for 'involved' (thesaurus). I am not certain of the 'in' bit.
'was about' is the wordplay.
I cannot quite see how this works, but
'about' could be 'on' and 'on' is found within the answer.
This may be the basis of clue (or it may be nonsense).
'to be' is the link.
Can you help me to learn more?
(Other definitions for concerned that I've seen before include "Involved - worried" , "Feeling or showing worry or solicitude" , "anxiety" , "Worried, anxious" .)