Spooky, unsettling (5)
I believe the answer is:
eerie
I believe this is a double definition.
'spooky' is the first definition.
(synonyms)
'unsettling' is the second definition.
(I've seen this in another clue)
(Other definitions for eerie that I've seen before include "Unnerving" , "Weird and disturbing" , "Unnatural" , "Frighteningly odd" , "Spooky, supernatural" .)