Join the staff (5)
I believe this is a double definition.
'join' is the first definition.
(I know that stick is a more specific form of attach)
'staff' is the second definition.
(I've seen this before)
'the' is the link.
(Other definitions for stick that I've seen before include "Join firm" , "Staff - criticism" , "Adhere; baton" , "Rod" , "Switch < put up" .)
'join the staff' is the definition.
(I've seen this in another clue)
This is the entire clue.