Inner workings shows courage (4)
I believe the answer is:
guts
I believe this is a double definition.
'inner workings' is the first definition.
(I've seen this in another clue)
'courage' is the second definition.
(I know that guts is a type of fortitude)
'shows' acts as a link.
(Other definitions for guts that I've seen before include "Belly; courage" , "backbone" , "Eat greedily" , "Stomach" , "Daring" .)