An artist whose work is arresting? (9)
I believe the answer is:
constable
'an artist' is the definition.
(painter John Constable)
I don't understand the rest of the clue.
(Other definitions for constable that I've seen before include "He painted" , "British painter and police officer" , "in blue?" , "Did he have a brush" , "English landscape painter for a policeman" .)