Hell-bent agent commandeers cab travelling north (7)
I believe the answer is:
fixated
'hell-bent' is the definition.
The answer and definition are different parts of speech. However, adjectives and past participle verbs can occasionally mean the same thing.
'agent commandeers cab travelling north' is the wordplay.
'agent' becomes 'fed' (fed is a kind of agent).
'commandeers' means one lot of letters goes inside another.
'cab' becomes 'taxi' (taxi cab).
'travelling north' is a reversal indicator (in a down clue, letters go up).
'taxi' backwards is 'ixat'.
'fed' going around 'ixat' is 'FIXATED'.
Can you help me to learn more?
(Another definition for fixated that I've seen is " Obsessive".)