End of novel otherwise ruined (4,3)
I believe the answer is:
done for
'ruined' is the definition.
(I've seen this before)
'end of novel otherwise' is the wordplay.
'novel' is an anagram indicator.
'otherwise' becomes 'or'.
'end'+'of'='endof'
'endof' with letters rearranged gives 'donef'.
'donef'+'or'='DONE FOR'
(Other definitions for done for that I've seen before include "Ruined" , "killed" , "Dead - almost dead" , "condemned" , "in serious trouble" .)