Celebrity directors? That's right (9)
I believe the answer is:
starboard
'right' is the definition.
(right side of a ship)
'celebrity directors?' is the wordplay.
'celebrity' becomes 'star' (a star is a celebrity or famous person).
'directors?' becomes 'board' (board of directors).
'star'+'board'='STARBOARD'
'that's' is the link.
(Other definitions for starboard that I've seen before include "right to 14 [YACHTS]" , "Ship's right side" , "Sailor's right" , "One side of a ship" , "Right side of ship or plane" .)