High-powered detectives arresting lots on the way back (7)
I believe the answer is:
dynamic
'high-powered' is the definition.
('dynamic' can be similar in meaning to 'high-powered')
'detectives arresting lots on the way back' is the wordplay.
'detectives' becomes 'cid'.
'arresting' indicates putting letters inside.
'lots' becomes 'many' (I've seen this before**).
'on the way back' says the letters should be written in reverse.
'cid' going around 'many' is 'cimanyd'.
'cimanyd' back-to-front is 'DYNAMIC'.
(Other definitions for dynamic that I've seen before include "Full of energy and ideas" , "Vigorous and go-ahead" , "Having power" , "I'm Candy (anag) - full of beans" , "Driving" .)