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 sure about the 'in' bit.
'was about' is the wordplay.
I cannot quite see how this works, but
'about' could be 'on' (as in a book 'on' a certain topic) and 'on' is found in the answer.
This explanation may well be incorrect...
'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" .)