The creative Mr Bridges who died for the cause (6)
I believe the answer is:
martyr
'died for the cause' is the definition.
I can't tell whether this definition defines the answer.
'the creative mr bridges' is the wordplay.
'the creative' becomes 'arty' (I've seen this before).
'bridges' means one lot of letters goes inside another (some letters go around or bridge others).
'arty' put into 'mr' is 'MARTYR'.
'who' is the link.
Can you help me to learn more?
(Other definitions for martyr that I've seen before include "put at stake?" , "Person who dies for a cause" , "Persecution victim" , "One suffering for conscience" , "One exaggerating suffering" .)