Hasten to hide US casualty in screen again (5)
I believe the answer is:
rerun
'screen again' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'hasten to hide us casualty' is the wordplay.
'hasten' becomes 'run' (I've seen this in another clue).
'to hide' means one lot of letters goes inside another.
'us casualty' becomes 'er' (I can't explain this - if you can you should give a lot more credence to this answer).
'run' enclosing 'er' is 'RERUN'.
'in' acts as a link.
Can you help me to learn more?
(Other definitions for rerun that I've seen before include "Broadcast or publish again" , "we've seen that before" , "Stand, for a second time" , "Repeat of, say, a film" , "Repeat (of race etc)" .)