Two men in Casualty (6)
I believe the answer is:
victim
This clue is a double definition.
'two men' is the first definition.
(Vic and Tim are men's names)
'casualty' is the second definition.
(both can mean someone injured or killed)
'in' acts as a link.
(Other definitions for victim that I've seen before include "One made to suffer" , "One is harmed or killed" , "A prey or sufferer" , "One who suffers the crime" , "One picked on" .)