Fascinated by unfinished story all told (2,5)
I believe the answer is:
in total
'all told' is the definition.
(I've seen this before)
'fascinated by unfinished story' is the wordplay.
'fascinated by' becomes 'into' (I've seen this before).
'unfinished' means to remove the last letter.
'story' becomes 'tale' ('tale' can be a synonym of 'story').
'tale' with its last letter taken away is 'tal'.
'into'+'tal'='IN TOTAL'
(Other definitions for in total that I've seen before include "Altogether" , "All told" .)