Man, crook? (5)
I believe the answer is:
staff
I believe this clue is a double definition.
'man' is the first definition.
(both can mean to work at a particular post)
'crook?' is the second definition.
(crook is a kind of staff)
(Other definitions for staff that I've seen before include "Employees; spindle in watch" , "Personnel or wooden pole" , "Take a rod to the personnel?" , "Employees; sceptre" , "support for notes" .)